He's 55-years-old ... but Jose Canseco ain't afraid to get into a dude's face when he feels disrespected -- and that's exactly what happened at Top Golf in Vegas.
Jose was swinging away with friends when a random man at the range came over to him and used his finger to signal Canseco to come out of his "Swing Suite" so they could talk.
Canseco felt the move was SUPER OFFENSIVE -- and proceeded to chew the guy out ... on camera.
"Wasn’t sure if he was trying to 'pick me up' or get an autograph," Canseco said about the encounter.