Harriett Reed Hackney, 42 a former director of government relations for the Prudential Insurance Co. of America, died of an apparent heart attack Monday while visiting a daughter in Wilson, Va.

Mrs. Hackney, who lived in Vienna, moved to Washington in 1969 and worked as a legislative aide for former representative Earl Ruth (R-N.C.). She then became executive director of the Republican Research Committee on Capitol Hill.

In 1975, she went to work for the Business Roundtable, an organization of business executives. She joined Prudential as director of government relations last September and resigned recently.

A native of Greensboro, N.C., Mrs. Hackney graduated from Duke University with a degree in political science. She was a probation counselor in the North Carolina court system before coming to the Washington area.

She was a member of Women in Government Relations, a professional group, and of the Capitol Hill Club.

Survivors include her husband, Charles W. Hackney Jr., and a son, Bobby, both of the home; four daughters, Margo Kinnett, of wilson, and Catherine, Blair and Carolyn, all of the home; her mother, Harriett P. Scurlock, and a sister, Gail P. Tillman, both of Greensboro, and one grandchild.

The family suggests that expressions of sympathy be in the form of contributions to the American Cancer Society.