The greatest duo in NBA history is BACK … stepping on the same court together for the first time in nearly 20 years.

Michael Jordan and Scottie Pippen joined up at MJ’s Flight School basketball camp Sunday night in Santa Barbara … gracing the hardwood with G.O.A.T.-level swag as they ran campers through shooting contests.

Jordan threw up some jumpers too — and the kids LOVED it.

The camp told us it was the first on-court meeting of the Bulls legends since their last title run in ’98 … one a lot of fans didn’t think would happen since they’ve never been too tight off the court.

Things seem cordial now. Take notes, LeBron and Kyrie.

Bonus: Sneak peek at MJ’s new all-white Jordans!Watch TMZ Sports on FS1