Harry Norwood Foss, 91 a retired assistant solicitor in the Department of Agriculture and a government employe for 40 years, died Sunday at Sibley Memorial Hospital following a heart attack. He had been hospitalized for prostate surgery.

Mr. Foss was born in Augusta, Me., He attended Shaw's Business College there and began his government career in 1909 as an employe of the Soldiers Home in Togus, Me.

The following year he moved to Washington and went to work in the old Land Office of the Interior Department. Mr. Foss went to night classes at th old Washington College of Law, now part of American University, and earned a law degree. In the 1920s, he joined the Department of Agriculture as an attorney and was an assistant solicitor at the time of his retirement in 1948.

Mr. Foss was a member of the old Sherwood Presbyterian Church, now the Northestern Presbyterian Church, in Washington. He served as an elder and as a trustee and sang in the choir. In January 1978, he and his wife, Edna, became residents of the Presbyterian Home in Silver Spring.

In addition to his wife, whom he married in 1911, Mr. Foss is survived by a brother, Kenneth, of Augusta, Me.