Dean K. Clowes, 58, a deputy undersecretary of Labor for international affairs from 1979 to 1981 and a former official of the United Steelworkers of America, died of cardiac arrest Thursday at George Washington University Hospital. He was a resident of Silver Spring.

Mr. Clowes began his union career as a CIO representative in Atlanta in 1948. From 1949 to 1953, he was a CIO adviser to the Marshall Plan, the aid program under which the economy of western Europe was restored after World War II, in Washington, France and Italy.

In 1953, he joined the Steelworkers as a representative in Canton, Ohio. He was assistant director of the United Steelworkers in Baltimore from 1956 to 1960 and then spent three years as the union's international affairs representative in Washington.

Mr. Clowes was deputy director of the AFL-CIO African-American Labor Center in New York from 1964 to 1968. He then returned to Washington and was director of the Steelworkers' political action and international affairs departments before joining the Labor Department in December 1979.

Mr. Clowes was a labor adviser in the Kennedy presidential campaign of 1960. In the 1964 campaign, he was a staff labor coordinator for vice president Hubert H. Humphrey and held a similar position in Humphrey's presidential bid four years later.

He was a member of the Charter Commission of the Democratic Party from 1973 to 1974. He served on the executive committee of the National Council on Aging and was a member of the labor advisory committee on multilateral trade negotiations.

Mr. Clowes, who was born in Pennsylvania, was a 1948 graduate of The Citadel in Charleston, S.C.

Survivors include his wife, Gladys, two daughters, Joan and Kathleen, and a son, Philip Dean Clowes, all of Silver Spring.