Robert Thomas Cochran, 59, a former assistant administrator of the Small Business Administration and assistant undersecretary of the Department of Transportation who also had been a newspaperman in Virginia and Texas, died Nov. 23 at Suburban Hospital after a heart attack. He lived in the Cabin John section of Bethesda.

Mr. Cochran was born in Dallas. He moved to the Washington area in 1946. A graduate of Georgetown University, he also earned a master's degree there in political science. He later studied law at George Washington University.

In 1951, he became an editorial writer with the Loudoun Times Mirror in Leesburg, Va., and in 1953 became editor of the paper. He later worked briefly as a speech writer for the late television and radio broadcaster Arthur Godfrey. From 1958 to 1961, Mr. Cochran was a writer and a special assistant to the editor of the National Geographic Magazine.

Mr. Cochran then moved to Houston and became the editorial page editor of the Houston Chronicle. He worked briefly in 1964 for the Democratic National Committee, where he wrote speeches for president Lyndon B. Johnson.

He moved back to Washington in 1965 and joined the Small Business Administration, where he became an assistant administrator. In 1967, he was an administrative assistant to former representative Robert Eckhardt (D-Tex.).

Mr. Cochran was the assistant undersecretary of the Transportation Department during 1968 and later was a consultant with the Social Security Administration and the Ford Foundation.

Since 1972 he had been a free-lance writer, consultant, and speech writer. His assignments included work as an assistant editor with the National Tourism Resources Review Commission and as editor of the 1976 report of the American Revolution Bicentennial Commission.

He had won the Virginia Press Association's Copeland Award for community service and the Texas State Bar award for editorial writing.

Survivors include his wife, the former Gloria Berg, of Cabin John; four daughters, Ellen Hicks and Cynthia Hayes, both of Washington, Sarah Shulman of Grayslake, Ill., and Jane Cochran of Cabin John; two sons, Stephen, of Check, Va., and Christopher, of Takoma Park, and five grandchildren.