The suspect punched the 70-year-old woman in the back of the head in an unprovoked attack, said police.
The video shows the man approach the victim who cannnot be seen entirely in the video.
She appears to fall. The man walks off eastbound on Parkside while raising his right arm.
Police said there was no interaction between the victim and the assailant prior to the assault in front of 148 Parkside Avenue on Jan. 16 at about 5:15 p.m.
The woman refused medical attention.
If you recognize the suspect or know anything about the incident that could help police find him, contact the NYPD Crime Stoppers at any of the following:
1-800-577-TIPS CrimeStoppers.com @NYPDTips on Twitter