Pavlyuchenkova, seeded third, had a tough outing against former French Open champion Francesca Schiavone of Italy but eventually prevailed 7-6 (11), 7-6 (6) in the other semi-final.
Top-seeded Radwanska continued her good form on her Seoul debut, having dropped just 11 games in four matches, and needed 64 minutes to thrash the Spaniard, ranked 113 in the world.
"It was definitely a very good match. I was playing really good tennis," said Radwanska, after reaching her fourth final of the year.
"It was really hot out there but I played my 100 percent throughout the match, so that's why it was two quick sets."
Pavlyuchenkova was hopeful that she could recover for Sunday's final after her gruelling semi-final that lasted two hours and 23 minutes.
"I'm so tired right now, to be honest," the Russian said after her victory. "I have to be aggressive but also consistent (in the final).
"We just played at the US Open and she's very consistent, she never misses, and if I make a lot of mistakes it'll be an easy victory for her," said Pavlyuchenkova who lost to Radwanska at Flushing Meadows last month.
"It will be a tough match for me, but it's the finals, and I hope I'll be 100 percent tomorrow (Sunday)."
Image: Agnieszka Radwanska
Photograph: Chung Sung-Jun/Getty Images
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