The following are the baseball events of the year 1982 throughout the world.
- January 9 - Tony Conigliaro whose career was ended in 1967 when he was hit by a pitch, suffers a massive heart attack on his way to the airport. The heart attack leaves Conigliaro in an unresponsive state of which he'd remain until his death in 1990.
- January 13 – Hank Aaron and Frank Robinson become the 12th and 13th players elected to the Hall of Fame by the Baseball Writers' Association of America in their first year of eligibility. Aaron fell nine votes shy of becoming the first unanimous selection, and his 97.8 election percentage is second only to Ty Cobb's 98.2 percent in the inaugural 1936 election.
- January 22 – Reggie Jackson signs with the California Angels, thus ending his five-year stay with the New York Yankees
- January 27 – The Chicago Cubs complete a trade with the Philadelphia Phillies that sees Iván DeJesús go to the Phillies for Larry Bowa, and Minor League prospect Ryne Sandberg also goes to the Cubs.
- February 8 – The Los Angeles Dodgers trade away Davey Lopes to the Oakland Athletics. This trade breaks up the starting infield of Lopes (second base), Ron Cey (third base), Bill Russell (shortstop), and Steve Garvey (first base), which had been together since 1974; the longest intact infield in Major League Baseball history.
- February 11 – In a trade of shortstops, the St. Louis Cardinals acquire Ozzie Smith from the San Diego Padres for Garry Templeton.
- March 10 – Former New York Giants shortstop Travis Jackson and former baseball commissioner Happy Chandler are elected to the Hall of Fame by the Special Veterans Committee. Jackson hit .291 in 15 seasons between the 1920s and 1930s, while Chandler was the second commissioner and oversaw – and encouraged – the dismantling of the color barrier in 1947.
- March 27 – The first game is played in the history of the KBO League, the major professional baseball league of South Korea.
- April 1 – The New York Mets trade Lee Mazzilli to the Texas Rangers for Ron Darling and Walt Terrell.
- April 6
- In Minneapolis, the Hubert H. Humphrey Metrodome debuts for major league baseball, as the Seattle Mariners outslug the Minnesota Twins 11–7. Dave Engle of the Twins christens the Dome with its first home run; third baseman Gary Gaetti, who earlier was thrown out trying to stretch a triple into an inside-the-park home run, adds two homers (over the fence) for the 52,279 in attendance. Muriel Humphrey, the widow of the 38th Vice President of the United States, threw out the first pitch.
- A blizzard unprecedented in size for April dumps 1–2 feet of snow on the northeastern United States, closing schools and businesses, snarling traffic, and canceling several major league baseball games.
- April 13 - It's opening day at Shea Stadium as the Mets behind Randy Jones beat Steve Carlton and the Phillies 5-2 before a crowd of 40,845, the highest opening day crowd at Shea since 1970. Dave Kingman went 2 for 3 including his 2nd home run of the season.
- April 20 – Before a crowd of 37,268—the largest crowd to see a game at Fulton County Stadium this season—the Atlanta Braves beat the Cincinnati Reds 4–2 to go 12–0, the best start ever by any Major League team. Steve Bedrosian was the winning pitcher. The streak would reach 13 the next day as the Braves beat the Reds 4–3.
- May 6 – Gaylord Perry of the Seattle Mariners becomes the 15th pitcher with 300 career wins.
- May 9
- May 25 – In the third inning against the San Diego Padres, Ferguson Jenkins, playing for the Chicago Cubs, becomes the seventh pitcher to record 3,000 strikeouts. His victim is Garry Templeton of the Padres.
- May 30 – Cal Ripken Jr. starts at third base for the Baltimore Orioles against the Toronto Blue Jays. It is the first game of his record-breaking 2,632 consecutive games played streak. Coincidentally, tomorrow, May 31, will be the fifty-seventh anniversary of the start of Lou Gehrig's streak, which Ripken will break.
- June 2 – The Milwaukee Brewers, 23–24 on the season and 7 games out of first place, fire Buck Rodgers as their manager. Harvey Kuenn replaces him and will guide the Brewers to victory in 20 of their next 27 games, the Brewers taking over first place on July 11. The team soon to be known as "Harvey's Wallbangers" will go on to win the American League East title and their only American League pennant.
- June 6 – While crossing a street in Arlington, Texas, umpire Lou DiMuro is struck by a car; he dies early the next day. Major League Baseball later retires his uniform number 16.
- June 20 – Pete Rose becomes only the fifth player in history to play in 3,000 Major League baseball games.
- July 13 – At Montreal's Olympic Stadium, in the first All-Star Game held outside the United States, Cincinnati Reds shortstop Dave Concepción hits a two-run home run in the second inning to spark the National League to a 4–1 win over the American League. It's the NL's 11th straight victory and 19th in the last 20 contests. Concepción wins the MVP honors.
- July 19 – Tony Gwynn of the San Diego Padres makes his Major League debut. His double and single will be the first two hits of the over 3,000 he will accumulate in his Hall of Fame career.
- July 29 – The Atlanta Braves were in first place in the National League West, 9 games ahead of the San Diego Padres when owner Ted Turner decides to remove the elevated tipi of mascot Chief Noc-A-Homa from the stands to allow more seats to be sold for the Braves' run at the division title. The Braves, however, lose 19 of their next 21 games, falling into third place before the tipi is restored.
- August 4 – Joel Youngblood of the New York Mets goes 1-for-2 off Ferguson Jenkins of the Chicago Cubs in a day game at Wrigley Field in Chicago. He is informed that he has been traded to the Montréal Expos, and leaves immediately for Philadelphia to meet the team there. He arrives in time to play, and enters the game in the sixth inning, getting a hit off Steve Carlton. He is the first player in Major League history to hit safely for two different teams on the same day.
- August 7 - In the fourth inning of a game at Fenway Park between the Boston Red Sox and the Chicago White Sox, 4-year old Jonathan Keane is hit in the head with a foul line drive hit into the stands by Dave Stapleton. The hit causes Keane's skull to bleed profusely, and Jim Rice quickly enters the stands and carries Keane inside the dugout to the Red Sox trainer's room, where team doctors take over. Rice plays the remainder of the game with a blood-stained uniform. Keane, meanwhile, recovers at a nearby children's hospital and Rice and the team doctors are credited with saving his life. After visiting Keane in the hospital, Rice stops by the hospital's business office and instructs that the family's bill be sent to him to pay.
- August 8 – Rollie Fingers earns the 300th save of his career, becoming the first pitcher in history to achieve that mark. He saves a 3–2 win for the Milwaukee Brewers vs the Seattle Mariners in Seattle.
- August 10 – For the first time this season, the Atlanta Braves are out of first place in the National League West. They lose to the San Francisco Giants 3–2 at Candlestick Park as the Giants' Milt May hits the game-winning home run off Al Hrabosky in the seventh inning; the loss is Atlanta's eighth consecutive and 12th in their last 13 games. Meanwhile, the Los Angeles Dodgers, who had trailed the Braves by 10 games less than two weeks earlier, defeat the Cincinnati Reds at Dodger Stadium 11-3 as Rick Monday and Steve Garvey both homer. The victory is the eighth consecutive and 12th in the last 13 games for the Dodgers, who had swept two four-game series from the Braves during this comeback—one at Atlanta–Fulton County Stadium at the beginning and another at Dodger Stadium (the first three coming in extra innings) just prior to the Cincinnati series. The Braves had been in first place since winning their first 12 games of the season.
- August 23 – Even though he has made no secret that he occasionally employs the spitball, Gaylord Perry is ejected from a game versus the Boston Red Sox for throwing the illegal pitch—the only such ejection in his career.
- August 27 – Rickey Henderson steals four bases, breaking the record he had shared with Lou Brock at 118 stolen bases for the season. He will steal eight more to end the season with a record of 130.
- September 5 – Roy Smalley of the New York Yankees hits a pair of three-run home runs, one from each side of the plate, as New York beats the Kansas City Royals 18–7.
- September 6 – Veteran first baseman Willie Stargell, whose jersey #8 is retired, is saluted by 38,000 fans on his day at Pittsburgh's Three Rivers Stadium. The 41-year-old slugger delivers a pinch single in the Pirates' 6–1 win over the Mets.
- September 12 – Minnesota Twins pitcher Terry Felton takes the loss today, his thirteenth of the year against no wins. He'll not pitch for a decision again. Coupled with his 1980 record of 0–3, Felton's 0-16 major league career sets a futility record for the most losses without a big league win.
- October 1 – Through seven innings, the New York Mets' Terry Leach and the Philadelphia Phillies' John Denny have each only given up one hit. Denny is lifted in the ninth for a pinch hitter, however, Leach remains in the game through the tenth inning without giving up a second hit. A sacrifice fly by Hubie Brooks in the tenth inning off Larry Anderson is the deciding factor in the Mets' 1–0 victory at Veterans Stadium.
- October 3 –
- At Baltimore's Memorial Stadium, The American League East Title was decided before an ABC television audience. Robin Yount hit two home runs and Don Sutton outdueled Jim Palmer as the Milwaukee Brewers beat the Baltimore Orioles 11–2 to capture the AL East Title. It was also to have been Earl Weaver's last game as an Orioles manager, but he would come out of retirement to manage the O's again from 1985 to 1986.
- At San Francisco's Candlestick Park, a 3-run home run by Joe Morgan helped the San Francisco Giants beat the Los Angeles Dodgers 5-3 and knocked the Dodgers out of the postseason and the Atlanta Braves became NL West Champions.
- October 6 – The Atlanta Braves and St. Louis Cardinals play four innings of Game 1 of the 1982 NLCS when rain halts play in the bottom of the fifth with the Cardinals batting, three outs away from being an official game, and the Braves ahead, 1–0. The rain does not subside and the game is called. The Cardinals would go on to sweep the Braves and reach the 1982 World Series.
- October 10 – After being down 2–0 to the California Angels, the Milwaukee Brewers complete a three-game comeback, defeating the Angels 4–3 to capture their only American League Championship. Fred Lynn of the losing Angels is named the Most Valuable Player of the Series after going 11-for-18 with 5 RBI and 4 runs scored. On the same date, the St. Louis Cardinals defeated the Atlanta Braves 6–2, to capture their first National League championship in 14 years. Darrell Porter was the MVP of the NLCS with his five-for-nine effort, including three doubles.
- October 12 –
- The first game of the 1982 World Series features Paul Molitor setting a new World Series record with five hits (in five at bats), as he leads the Milwaukee Brewers to a 10–0 victory over the St. Louis Cardinals in St. Louis.
- The Montreal Expos' Tim Raines enters treatment for drug abuse. Raines claims to have spent a fifth of his salary on cocaine when he stole a National League-leading 78 bases during the regular season, and says he started sliding head first to avoid breaking the vial of cocaine he kept in his back pocket.
- October 17 – In Game 5 of the 1982 World Series, a 6-4 Brewers victory, Robin Yount powers the Brewers with four hits, including a home run and a double. Along with his four-hit effort in Game 1, Yount becomes the first player ever to have two four-hit games in a single World Series.
- October 20 –
- October 26 - Steve Carlton of the Philadelphia Phillies won his 4th Cy Young Award, in that season he won 23 games, the ONLY pitcher to win 20 games in the 1982 MLB season.
- November 9 - Robin Yount of the Milwaukee Brewers was named American League MVP. During the Brewers' American League Championship season, he batted .318 with 21 home runs and 103 RBIS and even 19 steals.
- November 17 – Center fielder Dale Murphy wins the National League MVP Award, becoming the first Braves player to be so honored since Hank Aaron in 1957. Murphy hit .281 with 36 home runs, 109 RBI, 113 runs, and 23 stolen bases.
- November 22 – Second baseman Steve Sax of the Los Angeles Dodgers is named National League Rookie of the Year, becoming the fourth consecutive player from the Dodgers to win the award. Sax hit .282 and stole 49 bases as the replacement for Davey Lopes in the Dodgers infield.
- November 24 – Cal Ripken Jr., who hit .264 with 28 home runs and 93 RBI as a shortstop and third baseman for the Baltimore Orioles, is named American League Rookie of the Year. Ripken Jr. gets 24 of 28 first place votes, with the others going to Kent Hrbek of the Minnesota Twins.
- December 16 – The New York Mets send Lloyd McClendon, Charlie Puleo and minor leaguer Jason Felice to the Cincinnati Reds to reacquire Tom Seaver.
- December 21 - The dismantling of the long-time Los Angeles Dodgers infield continues as its most popular member, Steve Garvey, signs as a free agent with the San Diego Padres.