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 !