Diddy Checks Out Biggie Painting at Art Basel

Diddy's down in Miami for Art Basel this week, and already looking to expand his art collection with a Notorious B.I.G. painting worth around $20k ... TMZ has learned.

The mogul attended the hip-hop themed Avant Gallery exhibit at the Rockwell Wednesday night and took immediate interest in buying the 6 ft. painting of Biggie done by Miami street artist Zeem Rock.

Our gallery sources tell us although Diddy really liked the piece, and even posed with it ... he hasn't pulled the trigger yet.

The Biggie portrait was on display next to a Tupac mural, done by the same artist, but we're told Diddy didn't seem interested in that one.