Warren Jeffs' New Mug Shot Amid 'Keep Sweet' Netflix Documentary

Warren Jeffs, the subject of a popular new Netflix documentary, just posed for a new mug shot ... and he doesn't look happy about his streaming service fame.

The infamous president of the Fundamentalist Church of Jesus Christ of Latter-Day Saints is behind bars in Texas, where he's serving a life sentence for child sexual assault.

We're told Warren took his new mug shot Thursday ... as his Netflix doc continues to do big numbers. He's locked up at the Louis C. Powledge Unit ... a prison in Palestine, Texas.

The super-popular Netflix documentary, "Keep Sweet: Pray and Obey," takes a look at Warren and his controversial church ... where polygamy reigned supreme.

Warren reportedly had 78 wives when he was arrested back in 2006 ... and his rap sheet includes time on the FBI's Ten Most Wanted List plus a separate conviction for rape as an accomplice.