According to authorities, the victim was riding a northbound J train inside the Broadway Junction subway station when the suspect approached him and began yelling anti-gay slurs.
The suspect then punched the victim in the head several times. The victim sustained a bruised lip but refused medical attention.
Authorities say the suspect remained on the train and fled in an unknown direction.
The NYPD Hate Crimes Task Force is investigating the incident.
Anyone with information in regard to this incident is asked to call the NYPD's Crime Stoppers Hotline at 1-800-577-TIPS (8477) or for Spanish, 1-888-57-PISTA (74782). The public can also submit their tips by logging onto the Crime Stoppers website at https://crimestoppers.nypdonline.org/ or on Twitter @NYPDTips.
All calls are strictly confidential.