The Bizarro League, also known as the Bizarro Justice League, are the Bizarro version of the Justice League.
Bizarro stole Lex Luthor's imperfect Duplicator Ray to create a world of Bizarros. Some of these insane clones formed a Bizarro-version of the Justice League. This team enforced their twisted version of justice.
The Bizarro World was destroyed in Crisis on Infinite Earths along with the Bizarro League.
When the Joker got 99% of Mister Mxyzptlk's power as part of the Emperor Joker storyline, he recreated the Bizarro League and the Bizarro World. When the imp got his powers back, he kept the new "Bizarro World".
Bizarro gained "Bizarro Vision" (allowing him to make imperfect clones) under a blue sun. Bizarro planned to destroy the Bizarro World to be the reverse of Superman (because Superman would never destroy a planet). So the Bizarro-Lex Luthor led a revolt and unleashed the juggernaut Bizarro-Doomsday. The BL stopped the juggernaut by dropping a steel drum on him. However Bizarro ended up destroying the planet after all.
DC Super Friends: In issue #18, there was a Bizarro team called the "Bizarro Super Friends" based on the Bizarro League. Members were Bizarra, Bizarro, Bizarro-Flash, Batzarro, Bizarro Green Lantern (this version was the reverse of John Sewart), and Bizarro Aquaman. All of them, except Bizarro Green Lantern (the reverse of John Stewart), were based on the Silver Age versions of the characters. They are based in a mobile home in space.