The Bronx man accused of killing and dismembering his mother before taking a picture of himself with her severed head appeared in court yesterday wearing only a garbage bag.

At his bizarre appearance, Bahsid McLean, 23, also professed his innocence.

“I didn’t do anything wrong!” McLean blurted out after his lawyer asked for medication for him. “I don’t need anything at all. I didn’t do anything wrong.”

As for the trash sack, McLean “kept urinating on himself,” said defense lawyer Jerry Iannece.

McLean allegedly stabbed mom Tanya Byrd, 45, to death Tuesday, then dismembered the body.

McLean’s pal, William Harris, 26, also appeared in court on charges he helped chop up Byrd’s body and dump dispose of the parts in neighborhood trash.

McLean lived with his mother and 7-year-old brother in Morrisania.