The 64-year old proprietor of a popular Capitol Hill delicatessen was clubbed to death yesterday evening during an apparent robbery attempt that occurred when he returned to the restaurant after closing time.

Charles Solomon was struck in the head at about 6 p.m. inside the Delly of Capitol Hill at 332 Pennsylvania Ave. SE a few blocks from the Library of Congress, the House of Representatives office buildings and the U.S. Capitol.

People from all those buildings and elswhere on the Hill were among those who frequented the New York-style restaurant at lunchtime, and were among the customers and acquaintances who agreed with former employe Nadia Wolston in her evaluation of Solomon and his wife.

"When they liked you, you were just like family," Wolston told a reporter last night.

"He was the nicest man I've ever met," said an employe of a Capitol Hill tavern.

Solomon and his wife, who generally close the restaurant at 4 p.m., returned there yesterday evening on an errand. Mrs. Solomon waited outside in their car while her husband unlocked the restaurant and went inside.

About 10 or 15 minutes passed and Solomon did not emerge. Increasingly apprehensive, his wife finally left the car. She called police.

People on the busy commerical strip along Pennsylvania Avenue watched as officers arrived and entered the restaurant, carrying shotguns at the ready.

Solomon was found fatally beaten inside the restaurant that he and his wife had operated since the mid-1970's.

In the words of the terse statement issued late last night by the police department homicide unit, he was suffering from a head wound and the cause of death appeared to be "blunt force trauma." The motive was listed as attempted robbery.

There were no suspects.

Wolston, the former employe, found the death particularly poignant. "We always said he was going to have a heart attack," she recalled."He worked so hard. . . It's so sad that this is how he had to die."

Associates and acquaintances said Solomon had been a caterer in this area for many years before opening the restaurant. He had lived in Silver Spring for several years before moving at a Bethesda high-rise a few years ago. Within the past few months he had moved again, to another Bethesda address.

One of his new neighbors there, June Bray, said she remembered his as "happy, relaxed, outgoing."

She also remembered in particular how strongly he felt about his delicatessen.

"He was really proud of that restaurant," she said.