Roy G. Allman 73, a retired Washington lawyer who was active in Northern Virginia affairs, died Monday at Arligton Hospital after a heart attack. He had practiced law actively in Washington from 1940 until about 1970.

Born in Franklin Country, Va., Mr. Allman graduated from the University of Virginia Law School and was admitted to the Virginia Bar in 1931.

A year later, he joined one of his brothers, Norwood F. Allman in practicing law in Shanghai, Canton and Mukden, Manchuria. He remained in China wuntil coming here in 1940. He lived in Washington for 10 years before moving to Arlington.

In 1966, Mr. Allman gave a tract of land in Fairfax County, valued at $200,000 to George Mason College. He later was member of the "Communittee for 100 Acres" for the college.

He had been an unsuccessful candidate for a seat in the Virginia House of Delegates where another brother, John Brady Allman, had served for many years until his death in 1960.

Mr. Allman was a member of the Virginia Bar Association and was addmitted to practice before the U.S. Supreme Court.

He was part president and general counsel of the Society of Virginia, a member of the University of Virginia Alumni Association and of Calvary United Methodist Chruch in Arlington.

He is sirvived by his wife, Maxine Allman, and a daughter, Helen Allman, of the home in Arlington; another daughter, Janet Utter, of Columbus Junction, Iowa: three sons, Donald K., of Arlington, and Roy Wayne and John, both of Fort Lauderdale; two brothers, Judge N.F. Allman, of Boston, and three grandchildren.