The New Zealander, bidding to add a gold to the silver and bronze medals she won at the past two Olympics, is level at the top of the leaderboard with Switzerland's Morgane Metraux heading into the final round.
Ko said she watched "Rising", the docu-series which follows Biles' return to gymnastics after she struggled with a mental block at the Tokyo Games, before her third round.
"I watched her documentary and it was so inspirational," former world number one Ko told reporters.
"I think as an outsider, we never know what the person is going through. I think for her to have been so vulnerable, I think it inspires a lot of people and it inspired me.
"I loved a few of the quotes that she said so I kind of wrote it on my yardage book."
The 27-year-old Ko has previously said she will retire at a young age.
She became the youngest ever golf world number one aged 17 in 2015 and won her two major titles as a teenager.
"I think one of the things she (Biles) had is, 'I get to write my own ending'," added Ko.
"I always say, I want to be the one that's determining my fate and my ending and how I end my career, my round, and that just sunk in with me a lot."
