Kvitova, ranked 55th in the world, dominated the match and triumphed 6-3 6-2 to give herself a chance of a second title in 2009.
The 19-year-old won her first WTA Tour event at Hobart at the start of the year, however she has largely struggled to build on that.
Her notable victory over top seed Dinara Safina at the US Open suggested the left-hander could be a future top 20 player though, and the ease of her win over Radwanska emphasised her potential.
World number 10 Radwanska could not make her serve count and was broken six times in the one-sided clash.
After second seed Radwanska saw her title hopes dissolve, number three seed Yanina Wickmayer took out top seed Flavia Pennetta.
Belgian Wickmayer will take on Kvitova in the final after a 7-6 (7/5) 6-3 victory over Italian Pennetta who had two break points in the second set but took neither, while her opponent seized on her only chance.
Wickmayer has been usurped as Belgium's number one by the returning Kim Clijsters, however the 19-year-old is currently ranked 24th in the world after beginning the year at 67th.