A subway conductor was punched through an open train window in an unprovoked attack early Monday, police said.

The 31-year-old man was sitting in the conductor’s seat aboard an F train inside the Seventh Avenue station near West 53rd Street around 1:20 a.m. As the train was leaving the station, a stranger approached the open subway window and punched him in the face, police said.

The victim reported the random attack at the next subway station and was treated at Mount Sinai West for minor facial injuries.

Police are still looking for his attacker.

Additional reporting by Stephanie Pagones