Donald C. Stevens, 41, former county attorney for Fairfax County, died Sunday at Commonwealth Hospital.

He suffered head injuries last Oct. 5 when the car he was driving and a small van collided in Fairfax. He had been in a coma since.

Mr. Stevens served as county attorney from 1969 to 1972, when he joined the law firm of Hazel, Beckhorn and Hanes in Fairfax. He was a parter in the firm at the time of his death.

Born in Philadelphia, he graduated from the University of Florida in 1957. He came to Fairfax three years later to work as a claims adjustor for the State Farm Insurance Co.

Mr. Stevens also attended America University Law School, where he was presented of the legal fraternity, Phi Alpha Delta, and earned a law degree in 1965.

He then served as an assistant Commonwealth's Attorney for Fairfax County until becoming county attorney.

In that position, he was legal counsel to the Board of Supervisors. He won recognition for his endeavors to increase low-moderate income housing and for the settlement of the Burling tract. It was scheduled to be developed for the construction of homes but has remained a county parkland.

As a member of the Zoning Ordinance Study Committee, Mr. Stevens was involved in the drafting of the new zoning ordinance amendment, subsequently adopted in principle by the board.

Mr. Stevens was on the board of directors of the Heart Association of Northern Virginia, Inc. He was a former president of the Young Democratic Club of Fairfax and a member of the Fairfax County Democratic Committee.

He had served as counsel to the Northern Virginia Builders Association for the past five years.

He is survived by his wife, Sandra C. Stevens, and three children, Daniel G., Genevieve and Timothy, of the home in Alexandria; his mother, Grace F. Stevens, of St. petersburg, Fla., and a brother, Dr. David Stevens, of Boston.

The family suggests that expressions of sympathy be in the form of contributions to the Heart Association of Northern Virginia.