Drake just kicked off summer with an INSANE celebrity-packed pool party at his L.A. mansion Sunday -- with HUGE stars like Kanye, The Game ... and even Amber Rose!! 

But before you get any ideas ... no, we're told Kanye and Amber did NOT interact. 

But they did have a blast -- partying on Drake's massive property with somewhere between 500 and 600 of Drake's closest friends.

Among the stars in attendance ... French Montana, Blac Chyna, Travis Scott, Draya Michele, NBAers Brandon Jennings and Nick Young.

As for food ... typical BBQ fare ... burgers, dogs, wings and mac and cheese. There was also a full bar and a separate bar just for doing shots.

As one person who was there put it to us ... "Best party of the year so far."