The name Rainier (/rəˈnɪər/ or /reɪˈnɪər/; French: [ʁɛnje], a French form of Rainer) may refer to:

Given name

• Reginar II, Count of Hainaut (890–932), also written Rainier II
• Rainier, Margrave of Tuscany, Margrave of Tuscany from 1014 to 1027
• Rainier, Marquess of Montferrat (c.1084–1135)
• Rainerius (c. 1115/1117–1160), also spelled Rainier, patron saint of Pisa and travelers
• Renier of Montferrat (1162–1183), son-in-law of Byzantine Emperor Manuel I Komnenos
• Several princes of Monaco, of the House of Grimaldi:
  • Rainier I of Monaco, Lord of Cagnes (1267–1314)
  • Rainier II, Lord of Monaco (14th century)
  • Rainier III, Prince of Monaco (1923–2005)

Surname

• John Harvey Rainier (1847–1915), British admiral
• John Spratt Rainier (1777–1822), British rear-admiral and Member of Parliament
• Peter Rainier (Royal Navy officer, born 1741) (1741–1808), British admiral and Member of Parliament
• Priaulx Rainier (1903–1986), South African-British composer

Fiction

• Charles Rainier, main character in the novel Random Harvest by James Hilton
• Rainier Wolfcastle, an action hero star in The Simpsons episodes and comics