Cornelius Rice Parsons Cochrane, 80, who retired as an operations research official with the Social Security Administration in 1962, died Saturday at Suburban Hospital after a heart attack.

He was a native of Rochester, N.Y., and was a 1922 honors graduate of Amherst College. He attended Columbia University's law school. He came to Washington in the late 1920s to work for the American Association for Labor Legislation.

After serving as a labor consultant to various committees on Capitol Hill, Mr. Cochrane began his government career with the old National Recovery Administration in the 1930s. He was a field representative investigating alleged violations of labor laws.

He joined the old Social Security Board, later the Social Security Administration, when it was founded in the 1930s. In the 1940s, he was chief of the fiscal division of the Bureau of Employment Security.

During his later years with Social Security, Mr. Cochrane helped administer the organization's disability insurance program.

Mr. Cochrane, a resident of Potomac, had been a member of the Rockville and the River Road Unitarian churches.He was a former executive secretary of the Washington Ethical Society.

Survivors include his wife, the former Ida Rhea Pearson of Potomac; a son, Cornelius R.P. Jr., of Bowling Green, Ohio; a daughter, Donna Wonnacott of Potomac; a brother, Craig P., of St. Petersburg, Fla.; a sister, Jean C. Lane of Santa Barbara, Calif., and six grandchildren.

The family suggests that expressions of sympathy be in the form of contributions to the Rockville Volunteer Fire Department.