Scott Weiland’s ex-wife went nuclear when she was barred from taking some of his instruments from a recording studio in Burbank.

Cops were called to the studio where Scott’s ex, Mary Forsberg, was causing a scene while trying to make off with a keepsake.

Mary showed up with her and Scott’s teenage son. He wanted one of his dad’s guitars, but an employee of the recording studio refused to give them access.

After and argument started getting ugly, cops were called to calm everyone down.

Mary was told it was a civil issue and would need her lawyer to work out the problem.