James M. Head, 33, of 1509 16th St. NW was found guilty yesterday by a D.C. Superior Court jury of the murder, kidnapping and armed robbery of two Northeast Washington service station employes in December 1977.

Head who was employed as a barber at the time of the murders, was charged with the execution-style slayings of Edward Williams, 25, of 4482 Douglas St. NE, and Angelo Rowe, 24, of 4263 Nash St. NE. Both victims were found Dec. 4, 1977, lying face down, shot several times through the head.

Assistant U.S. Attorney Steven Gordon contended in the government's case that Head and two other men -- who have never been identified -- killed Rowe and Williams during an unsuccessful attempt to rob the safe at Morton's Amoco, 1536 Kenilworth Ave. NE, where the two slain men were employed.

George Morton Jr., owner of the service station, testified for the government that Head and the two other men came to his Fairmount Heights, Md., home about 3 a.m. on Dec. 5 and attempted to kidnap him at gunpoint. Morton said he escaped by jumping out of their car as it pulled away from his house.

Williams, who had been shot in the head three times, was found in Fort Dupont Park. Rowe, who had also been shot in the head, was found in an alley in the 400 block of 50th Street NE.

Head's attorney, Samuel Shapiro, contended that his client was playing cards in suburban Maryland on the night of the murders.