James Harden Mug Shot Revealed After Weapon Arrest

James Harden didn't look too thrilled to be posing for a mug shot early Saturday morning ... with the NBA star giving a blank stare after his gun-related arrest.

TMZ Sports has obtained the booking photo from the Houston Police Department ... showing the 36-year-old Cleveland Cavaliers guard staring down the camera lens.

As we previously reported, Harden was taken into custody around 3:41 AM when a handgun was observed on the seat of his car and not in a holster after being pulled over for a traffic violation.

He was charged with misdemeanor unlawful carrying of a weapon ... and was released after paying a $100 bond.

He has a court date set for later this month.

The Cavs said they were aware of the arrest and working on gathering more information.

Harden had 20.5 points, 4.8 rebounds, and 7.7 assists this past season ... playing half of the campaign with the Wine and Gold after a trade from the L.A. Clippers.