"This has been a remarkable tournament for me and to be in another final is a dream come true", said the top seed.
The top-ranked Djokovic was forced to produce his best tennis of the tournament to defeat Roberto Bautista Agut, 6-2, 4-6, 6-3, 6-2, who almost proved a disrupter in his first Grand Slam semifinal before succumbing to Wimbledon's four-time and defending champion.
"It was a really close opening four to five games of the third set that could have gone either way - thankfully it went mine".
He leads Federer 25-22 and Nadal 28-26.
The tensest, most thrilling of games followed, and after Federer fluffed a smash, Nadal squandered a break-back point.
Nadal carried that momentum with him and broke again two games later before serving out the set and levelling the match up after nearly 90 minutes on court.
There would have been concerns for Federer fans when he skewed a forehand high into the crowd, yet he was calmness personified in the third, racing across the turf and aggressively moving a set away from another final.
Nadal saved two break points at 1-1 in the second set before breaking Federer twice in a row and serving it out at love.
Djokovic fought off two break points, via a 23-shot rally, in the fifth game.
Novak Djokovic beat Roberto Bautista Agut, 6-2, 4-6, 6-3, 6-2, to reach a Grand Slam final for the 25th time.
In the third, Djokovic broke for a 4-2 lead and then saved two break points in the next game - the second with a backhand victor down the line after a 45-stroke rally.
The set was secured, ironically off another net cord which fell this time in the Serb's favour.
Djokovic was broken once in the second set, allowing Bautista Agut to even the score. There are a variety of other Wimbledon odds you can target like the game spread, where Nadal is favored by 1.5.
Rafael Nadal walks off the court after his four-set loss to Roger Federer. But Federer won the set 6-4 to take the match. By ranking (22nd), he should not have presented much of a threat to Djokovic, who had won three of the previous four Grand Slams.
Nadal, the 2008 and 2010 champion at Wimbledon, has the edge overall, leading his great rival and friend 24-15 and 10-3 at the Slams.
Nadal tried to stay alive in the fourth set, pushing Federer to match point five times.
When is the semi-final clash between Roger Federer vs Rafael Nadal Wimbledon 2019? He's arguably the top Wimbledon player of all time, entering this match an astonishing 100-12 in this tournament with eight titles, the most recent coming in 2017.
Federer, 37, is the oldest man in the semi-finals of a Slam since 39-year-old Jimmy Connors at the 1991 US Open.
A buzz of anticipation over another epic showdown could be felt around the All England Club from the moment two legends sealed their passage into the semi-finals.
Roger Federer has won the first set 7-6 (3) in his Wimbledon semifinal against Rafael Nadal.