A 15-year-old who was punched in the face by an NYPD cop last week during a wild brawl at a Brooklyn subway station that was captured in viral videos plans to sue the city for $5 million.

Benjamin Marshall filed a notice of his intention to sue Wednesday, claiming he was “doing nothing wrong” when a melee broke out in the Jay Street-MetroTech station on Oct. 25 between a group of teens and a dozen officers from the 84th Precinct.

Marshall’s father, Anthony Noel, said at a news conference that his son was headed into the subway station to retrieve his backpack when he was slugged by a cop.

“While he was there he was punched multiple times by one of New York’s Finest — which should never happen,” Noel said. “If you look at the video you would see he was laying on the ground. There were about six cops on his back. One had his knee on his neck. Benjamin was crying out ‘I can’t breathe, I can’t breathe, I can’t breathe.’ ”

Police were initially called to the station for reports of a fight between two groups that then spilled into the Downtown Brooklyn transit hub.

According to medical reports that Rubenstein distributed to reporters, Marshall suffered a concussion from the incident.

Victoria Noel, Marshall’s mother, claimed her son was held by police for 11 hours without medical attention.

Marshall was accused of decking an officer in the face, his mother said — a charge that Marshall denies.

The teen’s lawyer, Sanford Rubenstein, said there is a pending criminal complaint against Marshall for the alleged assault but the city’s Corporation Counsel — which brings cases in Family Court — has not yet determined if it will officially charge him.

The NYPD didn’t immediately respond to request for comment on whether he is facing charges or the other allegations in his suit.

At a news conference on Wednesday, Police Commissioner James O’Neill declined to comment on the case directly but said the matter is under investigation.

“The officer involved is on non-enforcement duty,” O’Neill said. “But first and foremost, there shouldn’t be any fighting on subway platforms, especially by teenagers, because it is in an inherently unsafe place.”

Several pols, including Brooklyn Borough President Eric Adams — who is himself a former cop — and City Council Speaker Corey Johnson, have called for a formal investigation into the incident.

In the wake of the fight, an unidentified police officer who was caught throwing punches was transferred from the 84th Precinct to the Brooklyn detective squad, sources told The Post. The officer has been the subject of several reports filed with the Civilian Complaint Review Board — some of which were for use of force issues, sources said.

The city’s Law Department declined to comment on the notice of claim.