Juan Romero, the hotel busboy who came to the aid of Senator Robert F. Kennedy when he was shot in Los Angeles in 1968, died on Monday in Modesto, Calif. He was 68.

His longtime friend Rigo Chacon, a television newsman, told The Los Angeles Times that Mr. Romero had apparently had a heart attack several days earlier.

Mr. Romero was a teenage busboy working in the kitchen of the Ambassador Hotel in June 1968 when Kennedy, moments after giving a victory speech in the California Democratic primary, came walking through and was shot in the head by an assassin.

Mr. Romero rushed to Kennedy and held him as he lay on the floor mortally wounded. Mr. Romero later said he had struggled to keep the senator’s head from hitting the floor.