Ronnie Ortiz-Magro walked out of the club dabbing his face with a tissue after Jen Harley allegedly nailed him with an ashtray … this according to surveillance footage.

In the video — obtained by TMZ — you see Ronnie leaving the Hustler Club in Vegas just a little before midnight on New Year’s Eve without his baby mama. You can see the “Jersey Shore” star dabbing blood off his face in the clip.

Sources at the club say the two arrived together in good spirits … so it’s clear something went down.

We broke the story … Ronnie filed a battery report with police against Jen over the incident, alleging she hurled the ashtray in his direction during their argument and struck him in the face, cutting his nose, lip and forehead.
via Tmz