The Serb, who lost his number one ranking to Nadal in October, was too solid for Wawrinka in the day's second semi-final as he racked up a 14th consecutive victory over the 28-year-old.
Djokovic used all his defensive skills in the eighth game of the first set to convert a break point for a 5-3 lead and took the opener with an ace.
Wawrinka, who has made the semi-finals on his debut appearance at the season-ending showpiece, hung on grimly in the second set after dropping serve but Djokovic was clinical as he stretched his winning streak to 21 matches.
In the first semi-final Nadal beat Wawrinka's fellow Swiss Roger Federer 7-5 6-3.
Djokovic, who like Nadal had a 100 percent record in round robin play, will be desperate to retain his title after ceding the world number one ranking to the relentless Spaniard in October.
"We are both having a great season this year. This is probably the best possible final we have here in London. We'll see what happens tomorrow," Djokovic, who was rock solid against tournament debutant Wawrinka, told a news conference.
"This is probably the most competitive tournament that we have after grand slams in our sport, and we both want to end this season in the best possible way and end it with a title."
Wawrinka, who twice pushed Djokovic to five-sets in the year's standout matches at the Australian and U.S. Opens, held on grimly in the second set but could only applaud at one point as Djokovic somehow reached a certain winner and clawed a forehand across the bows of the in-rushing Swiss.
Two breaks in the second set completed the Djokovic masterclass and a 14th consecutive win over Wawrinka.
"I didn't have enough energy today...against him, that makes a big difference," Wawrinka said.
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