Michael Jackson and the woman who played his girlfriend in the "Thriller" music video could cut through their sexual tension with a knife when they were filming ... at least according to her.

Ola Ray, a former Playmate and music video vixen, sat down with TMZ's very own Charlie Neff ... recalling her interactions with MJ back in the 80s.

There's a part in the music video where Ola kisses Michael -- and she tells us about their flirty conversations leading up to the scene.

Ola says she crossed paths with Michael in the years that followed, and he even asked her out to lunch ... she passed on the offer, but gave the King of Pop her phone number and told him to call ... and she explains why that was a regrettable choice.

Despite the sexual chemistry, Ola sued Michael and his production company in 2009 -- one month before Michael's passing -- claiming she wasn't paid royalties for the legendary video.

Ola settled her case with his estate in 2013, winning $55K for herself and $20K to her attorney ... and now she says there were never any hard feelings with Michael.

Check out Ola's full interview with Charlie ... they also get into the new "Michael" bipioc ... and Ola shares her thoughts and honest reaction.

Thriller, thriller night!!!