Boss of All Bosses is the second studio album by American rapper Slim Thug. The album was released on March 24, 2009, by Boss Hogg Outlawz and E1 Music. The album was met with generally favorable reviews from music critics and publications upon its release. The album debuted at number fifteen on the U.S. Billboard 200 chart with 32,000 copies sold in its first week released.
Boss of All Bosses received a generally positive reception from music critics who saw it as an improvement over his major label debut Already Platinum. David Jeffries of AllMusic praised the album for being a return to Slim's early mixtape years, concluding that "this raw album is a welcome throwback that no longtime fan should be without." Pedro 'DJ Complejo' Hernandez of RapReviews praised the production for being a return to the Southern sound and Slim for expressing his voice through different topics throughout the whole album, saying that it "sounds like the triumphant introduction to Thug's unique brand of Texas rap rather than Thug trying to conform to the current trends." DJBooth gave a mixed review of the album, saying that some of the songs' lyrical material and production was given some flair but the others felt by-the-numbers despite Slim's performance, concluding that, "All things considered, Slim Thug can still maintain his administrative position in the game despite this sophomore slump."