New York Police Department spokesman Paul Browne says investigators recovered security video showing a man fitting the description of the assailant working with street vendors near Rockefeller Center.
Police went there Tuesday and took him into custody.
Ki-Suck Han of Queens died shortly after being hit by a train Monday at the Times Square subway station.
Police say he tried to climb a few feet to safety, but got trapped between the train and the platform’s edge.
Subway pushes are unusual. Among the more high-profile cases was the January 1999 death of Kendra Webdale. A former mental patient admitted he shoved her to her death.