Cops are searching for a vandal who scrawled anti-Semitic graffiti on a scrolling message board outside an Upper East Side synagogue.

The suspect, who has not been identified, walked up to the Congregation Kehilath Jeshurun Synagogue at 125 East 85^th Street at about 7 p.m. Saturday, took out a marker and graffitied a display screen attached to the house of worship, the NYPD said.

Police described him as a man with a slim build and short black hair who is around 25 years-old.

He wore a white tank top, camo shorts and white sneakers, and ran off on East 85th Street after the hateful act.

By Sunday morning, the writing had been wiped off.

The sign suffered no damage.

“It was pretty easy to wipe off – they got it clean in a few minutes,” a neighbor named Scott told The Post.

“There’s three cameras right there!’ Scott, 51, continued. “Guy was probably wacked out on drugs. We get a lot of that here.”

The synagogue remained empty — even though there was a service scheduled for 9 a.m.

The NYPD’s Hate Crimes Task Force is investigating, cops said.

The department is asking anyone with information 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 tips by logging at https://crimestoppers.nypdonline.org/.