Two vacationing Israeli police officers were robbed of $50 and severely beaten last night by three youths who accosted them as they were walking in Northeast Washington near Catholic University, D.C. police said.

The Israelis, identified as Nachun Adan, 32, and Nathan Zeldes, 27, were listed in fair condition at the Washington Hospital Center early today. Adan suffered injuries to his legs, chest and head and Zeldes had a fractured hand, hospital spokesmen said.

Police said the incident occurred about 10:30 p.m. as the two men were walking in the 2600 block of Fourth Street NE, 10 blocks from their hotel at Monroe Street and Michigan Avenue NE.

The men were first approached by two youths who asked them for cigarettes, and when the Israelis complied the youths left, police said.

Moments later, police said, the two youths, joined by a third, ran up to the Israelis from behind, struck both of them with iron pipes and demanded money.When the Israelis resisted, police said, the youths continued beating them until they wrested Adan's wristwatch and wallet from him. The robbers then fled.

Police said the two Israelis, both of Jerusalem, had been visiting Washington after attending a law enforcement seminar in Boston.

No arrests had been made as of early today.