World number one Nadal, an eight-time Roland Garros winner, did not concede a single break point in a one-sided encounter on Court Philippe Chatrier, sinking the seventh seed with a series of forehand winners. (Agencies)
Murray, looking to become the first British male to reach the Paris final since tennis went professional in 1968, was never in the contest and made too many unforced errors on his usually reliable forehand.
Nadal wrapped up victory on his first match point with a smash on the Scot's serve.
"I think I played some of my best tennis at Roland Garros today," said Nadal after extending his French Open record to 65 wins and one defeat.
"I'm very emotional to reach the final again," he told reporters. "It's a dream. Novak is an unbelievable opponent," he said.
World number two Djokovic, who earlier beat 18th-seeded Latvian Ernests Gulbis in the other semi-final, is one of three men who have beaten Nadal on his favoured red dirt this year.
Nadal slammed 24 winners, most of them with his forehand, against a helpless Murray and converted all six break points he had.
"He played a great match. He missed hardly any balls. He served very well," said the Scot.
"His forehand, especially with the conditions the way they were today, was incredibly hard to control. As soon as he was inside the court he was hitting the ball so close to the line,” he said.
Nadal's uncle and coach Toni agreed with Murray. "I think he played one of his best matches at Roland Garros," said Toni.
In hot weather that favoured the Spaniard's top spin, Murray won only 10 points on his opponent's serve.
Nadal raced into a 3-0 lead after breaking in the second game when his opponent netted a forehand.
Murray held for the remainder of the set but could not trouble the Spaniard on his serve and Nadal bagged it with a casual forehand volley.
In the third game of the second set the man from Mallorca broke when Murray sent an easy forehand wide.
Nadal turned the screw in the seventh game, stealing Murray's serve again as the world number eight made yet another unforced forehand error.
The top seed, who has an 88-1 record in best-of-five set matches on clay, quickly put the Scot out of his misery in the final set to reach his fifth consecutive Roland Garros final.
World number one Nadal, an eight-time Roland Garros winner, did not concede a single break point in a one-sided encounter on Court Philippe Chatrier, sinking the seventh seed with a series of forehand winners.