Ding lost 18-14 to Selby in Sheffield earlier this year, and will hope to gain some revenge as he heads into Sunday's final in Shanghai off the back of a 6-3 win over Stephen Maguire.
Maguire took an early lead only for Ding to fight back, but the Scot got his nose in front as he claimed the first frame after the interval.
After that, however, Ding consistently came out on top of what degenerated into a fairly scrappy match, with breaks of 58, 47, 46 and 44 enough for him to win the final four frames in a row.
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"We both played well during the first half of the match,” said Ding.
"Stephen missed some later on and left me chances. It seems like I’m getting better match by match.
"I felt comfortable out there without pressure and I wasn’t worrying about the outcome. I think I’ll play my own rhythm in the final tomorrow.
"In the World Championship final I was trailing from the early stages and in fact I did pretty well on the second day, which I can learn from and get prepared for tomorrow.”
Earlier on Saturday Selby came through a final-frame decider against former World Champion Stuart Bingham.
Bingham took a 5-3 lead in the match thanks to breaks of 67, 123, 72 and 87 in consecutive frames, and seemed destined for a spot in the final.
But Selby continued to grind in his inimitable style as he scrapped his way back into the match at 5-5 before dominating the decider.
"I’m delighted to be in the final here again,” said world number one Selby, who - like Ding - is bidding to become the first player to win the Shanghai Masters twice.
"It was a very difficult match because Stuart played great. I felt I was in control at 3-1 but then I played one bad safety shot in the fifth frame and he barely missed a ball for the next four.
"I’ll just prepare for tomorrow, come back fresh and give it by best. I love coming to Shanghai and hopefully I can win the title here for a second time."
Bingham was distraught after letting slip his big lead.
"I’m absolutely gutted. I had a couple of chances to win 6-3. It will take a few months to get over this defeat," he said.
"I felt like the stronger player when I went 5-3 up, then Mark showed grit and determination as he always does.
"At 5-3 I had a blue into the green pocket and someone in the crowd coughed and I missed it. For the rest of that frame my concentration wasn’t there.”
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