Dustin Diamond: Screech Checks Into The Big House

Dustin Diamond is officially an inmate ... turning himself into a Wisconsin jail Friday night.

Diamond reported to the Ozaukee County Jail to serve out a 4 month sentence. You'll remember, Diamond was convicted back in May for stabbing a man in a bar on Xmas of 2014. Lucky for Dustin, the judge only hit him with 2 misdemeanors and dropped the far more serious felonies.

Not so good news ... Dustin checked in after dinner time at the jail. We're told Friday's menu was country fried steak, gravy, rice, salad and a piece of cake.

No telling if the sentence will be one too.