UFC fighter Angela Magana says Cris 'Cyborg' Justino is gonna pay for punching her in the face this past weekend ... telling TMZ Sports she's lawyer'd up and is ready to sue.

We spoke to Magana who says she's "most definitely" suing Cyborg for her medical bills and has been cooperating with authorities ... who she claims are pursuing felony assault charges.

(As of now, Cyborg has only been cited for misdemeanor battery.)

Angela also calls B.S. on people who say she had it coming after taunting Cyborg online ... saying Justino needs to have thicker skin.

Magana also sent a message to Cyborg.

"You f***ed up, big time. You can't do what you did. I'm gonna get you as hard as I can get you."