The 24-year-old, World No.77, reeled off the last four games of the match, holding her own confidently against a frustrated and emotional Bencic, reports Efe.
She fired 42 winners to Bencic's 26 and won the match 7-6(2), 4-6, 6-2 after a two-and-a-half-hour battle.
"I still can't believe it, because I was not expecting this at all," Schmiedlova said after the match.
"Especially tough today against Belinda - I've known her since I was a child, we practice together sometimes and she's a really good friend of mine. So it wasn't an easy match. She's a great player, but it's a really great feeling the way I played," she added.
Bencic had begun the match confidently. However, it was Schmiedlova who claimed the first break at 4-2.
She dominated the tiebreak, allowing her opponent just two points as she won the opening set.
Bencic played better in the second set, which she won, sending the match into a decider.
"I think I improved a bit on my serve, and just tried to be focused on every point. I think that third set was really good, better than the first for me," Schmiedlova said.
"I lost in China, playing very bad, then I came here and it was really windy. I didn't really play very well in practices, so I tried to just win maybe one match here or play one long match. To be in the final, I never expected it," she added.
(This story has not been edited by Business Standard staff and is auto-generated from a syndicated feed.)