He needs to get locked up!

A crazed bicyclist attacked a 59-year-old driver with his bike lock in Greenpoint Monday evening, striking him in the head and breaking his side view mirror, police said.

The bicyclist and driver were arguing over a traffic dispute when the biker ditched his bike and starting whacking the victim’s 2014 Toyota Prius with his bike lock, cops said.

The bitter biker opened the driver’s door and hit the man in the head before striking him directly in the head with the bike lock, according to police.

He rode off on his bike while his bloodied victim waited for an ambulance, police said.

He was transported to Bellevue Hospital and treated for a laceration to the head and the hand, cops said.