Dr. Howard Stone Anderson, 75, pastor emeritus of the First Congregational United Church of Christ here and a longtime trustee of Howard University, died of a cardiac arrest Aug. 25 at his home in Stamford, Conn.

Dr. Anderson was serving as interim pastor of the Stamford Congregational Church at the time of his death.

Long identified with the civil rights movement, Dr. Anderson was chairman of the executive committee of Howard University's board of trustees for 19 years. He served on the board itself for more than 30 years.

He served as pastor of the First Congregational Church twice, from 1936 to 1947 and again from 1968 to 1970. The church, founded in 1865, helped found Howard University in 1867 when a member, Gen. Oliver Otis Howard who headed the Freedman's Bureau after the Civil War, proposed the university be established The institution is named for Gen. Howard.

Dr. Anderson was an outspoken commentator on social issues during his first pastorate here and spoke out for civil rights during the late 1960s, when he chaired an ad hoc committee on student relations at Howard University. He also was a trustee of Dillard University, a black school in New Orleans.

He had been pastor of churches in New York, Massachusetts, Illinois, North Dakota, Wisconsin, Virginia, New Jersey and Florida during his 53 years as an ordained minister.

Dr. Anderson graduated from the Chicago Theological Seminary and received an honorary doctor of divinity degree from Doane College in Nebraska.

He was a member of numerous church and religious organizations, including the American Missionary Association, the International Council of Congregational Christian Churches and the Washington Ministerial Union.

His wife of 53 years, Marlowe Addy Anderson, also an ordained minister, died in January.

Survivors include three daughters, Dr. Polly Graham of Moorestown, N.J., Marlowe Kidston of Park Ridge, Ill., and Chloe Nassau of New York City and Stockbridge, Mass., and six grandchildren.

The family suggests that expressions of sympathy be in the form of contributions of the Marlowe and Howard Stone Anderson Fellowship at Howard University.