The win sees Osaka book her place in the final, a remarkable turnaround from her showing at Indian Wells.
Bencic took the first set 4-6, before the 24-year-old won the second and third 6-3 6-4.
The former world number one was visibly emotional after sealing her place in the final.
“Damn, I’m almost crying,” Osaka said after the win. “This tournament means a lot to me.
“It’s my first time in the final here and I’m really thankful. It’s been a while since I’ve been in a final – I think it was the Australian Open last year – so thank you guys so much, I really love you from the bottom of my heart.”
Osaka will now face Polish star Iga Swiatek in the final.
Iga Swiatek vs. Naomi Osaka for the #MiamiOpen title.
This will be the first match since the two met for the 1st time at 2019 Toronto.
In the electric encounter, Osaka won 76 64. pic.twitter.com/9EUc06dvcz
— WTA Insider (@WTA_insider) April 1, 2022
20-year-old Swiatek is yet to drop a single set so far in this tournament.
And now she’s looking forward to taking on Osaka in a battle to win the title.
“I am excited for sure [about facing Osaka in the final], but on the other hand for me, the most important job is this is a match like any other,” Swiatek said.
“I don’t want to change my routines, I don’t want to change my attitude, because it’s been working out pretty well. I’m going to treat it like any other match.”
The women’s singles final will take place tomorrow, April 2.