DJ Khaled Lost His Mind Celebrating Miami Heat Win, 'WE IN THE FINALS!'

DJ Khaled went ballistic celebrating the Miami Heat's win over the Celtics on Sunday ... jumping and screaming like a mad man -- and the whole thing was caught on video!!!

The 44-year-old -- who's been a Heat fan for YEARS -- was catching the NBA's Eastern Conference Finals game in a living room somewhere ... when Miami pulled out the series win.

That's when Khaled went CRAZY ... grabbing his drink, woooooing like Ric Flair and hopping around like a little kid!!

Ya gotta watch the clip ... the dude is SUPER PUMPED for his favorite team -- and said of the victory afterward, "WE IN THE FINALS !!!!!!!!"

Khaled then gave an epic pump-up speech about his squad ... boasting about all their championships and saying straight-up the air conditioning in Miami's locker room "pours out greatness!!"

Of course, the celebration might be short-lived ... the Heat have a tough road ahead of it in the NBA Finals -- as LeBron James and Anthony Davis await.