A stranger slashed a woman in the face outside Harlem’s historic Apollo Theater on Monday evening, police said.

The 43-year-old woman was walking toward a train station around 8:30 p.m. and was in front of the theater at 253 W. 125th St., when a man walked up from behind and slashed her near the right temple with an unknown sharp object, police and sources said.

The pair did not exchange words before the unprovoked attack, police said.

“They walked passed each other,” a police spokesman said. “He doubled back and slashed her from behind.”

The victim was taken to Harlem Hospital, where she received seven stitches.

Police describe her attacker as a 6-foot-tall man with a skinny build, who was last seen wearing brown pants and a bubble jacket.

Additional reporting by Stephanie Pagones