Nadal, seeded second, won in straight sets, 6-4, 7-6 (1), 6-2, over eighth-seeded Richard Gasquet, who has yet to defeat the Spaniard in 11 matches. Gasquet double faulted on the final two points of the match.
Nadal, who has won 12 Grand Slam singles titles in 17 finals, pumped his fists and threw tennis balls into the stands to celebrate.
"This is just amazing," Nadal said. "Have a chance to play the final Monday, just thank you very much for the support."
Nadal said Djokovic is "an amazing competitor" and added, "He's a great champion. It will be a tough final for me."
The 27-year-old broke the Frenchman in the opening game of the first set. Much of the Arthur Ashe Stadium crowd had left after the first semifinal, in which Djokovic needed five sets and 4 hours 9 minutes to defeat ninth-seeded Stanislas Wawrinka, so there was little atmosphere.
Sean Connery and Ben Stiller did watch the second semifinal, though, sitting side by side.
Gasquet, coming off consecutive five-set wins over Milos Raonic and David Ferrer, earned a break point in the fourth game against Nadal, who had held serve in 83 consecutive games starting in Cincinnati last month.
But Nadal saved the break point with a big forehand for deuce and held for the 84th straight time with the help of an ace. That gave him a 3-1 lead, and he would go on to take the set, 6-4, finishing with his 72nd straight service hold at the Open.
The Spaniard opened the second set the same way the first set had started, breaking Gasquet's serve for a 1-0 lead.
In the next game, however, Nadal faced two break points, and on the second he got broken by sending a forehand long -- the first time he lost serve in 88 games. And with the break Gasquet tied the second set at 2-2.
In the eighth game Gasquet got another two break points with a backhand return, but Nadal saved both, with an ace and a service winner, and held for 4-4.
The two then exchanged service holds and went to a tiebreaker.
Gasquet opened the tiebreak with a double fault and that set the tone. He would win only one point and he closed the tiebreak with another double fault to give Nadal a 6-4, 7-6 (1) head start to the final against Djokovic.
Nadal had to save a break point in the first game of the third set but ended up holding for a 1-0 lead. The Spaniard earned a break point in the next game and capitalized when Gasquet mishit a backhand off a tough Nadal service return. Nadal now had a 6-4, 7-6 (1), 2-0 lead and seemed well on his way to the final, a spot that became even closer when Nadal held at love for a 3-0 lead.