The Czech, ranked 42nd in the world, won 10 of the last 12 games of the match, guaranteeing her country their best finish ever in singles play at the Olympics after Jana Novotna and Petra Kvitova previously won bronze.
Vondrousova routs Svitolina to book spot in final
The two women traded breaks to begin the match before Vondrousova held two break points at 15-40. Svitolina saved both of them, but presented with a third chance, she was handed the lead after a double fault by Svitolina.
Ahead 3-2, the Czech posted two confident holds to move to within a game of the set at 5-3. She hit a forehand winner down the line to bring up set point and when Svitolina missed on a chip forehand, Vondrousova took a one-set lead.
She continued her momentum heading into the second set, breaking Svitolina after the Ukrainian missed a backhand into the net to take a 2-0 lead. An easy hold got her to 3-0 and she was on her way to the final.
Svitolina held to stop the run of four consecutive games by Vondrousova, but the Czech broke when the fourth seed dumped a forehand into the net. Serving for the match at 5-1, Vondrousova closed out the victory with another imperious forehand.