A cellphone photo that a brave 15-year-old girl snapped of a man who allegedly stalked and grabbed her on a Brooklyn subway platform led to the suspect’s arrest Tuesday.

Raheen Reid, 29, grabbed the teen’s arm as she waited for a train at the Atlantic Avenue station at about 8:15 a.m. Dec. 9, cops said.

Reid, of Crown Heights, allegedly tried again six days later when he saw her.

That time, the savvy teen used her cellphone to take his picture, and gave it to police, authorities said.

A tipster led to cops charging Reid with attempted kidnapping and stalking.