Harold M. Devlin, 86, assistant to the president and chairman of the board othe Curtiss-Wright Corporation, died of cancer Friday at Mt. Vernon Hospital in Alexandria.

Mr. Devlin, who lived in Alexandria, was born in Mahoney City, Pa., and grew up there and in Philadelphia. He graduated from St. Joseph's College in Philadelphia.

During World War I, he worked at a Philadelphia shipyard and later for a number of businesses in that area.

In 1936, he joined the Securities and Exchange Commission in Washington as an accountant. He settled permanently in the area four years later. In the early 1950s, he spent two years on loans as a staff investigator for the Senate Armed Forces Preparedness Subcommittee, chaired by the then-senator Lyndon Johnson.

He joined the Curtiss-Wright Corporation about 1953 and remained active with the company until his death. Besides assisting the president and chairman of the board, he represented the company in legislative matters.

Usrvivors include his wife of 64 years, Regina Marie of Alexandria; two daughters, Doris Barnsley, also of Alexandria, and Nancy Murphy of Wilmington, Del.; three sons, John of Pasadena, Calif., Harold Jr. of Bowie, and Daniel R. of Rockvill, 14 grandchildren, and nine great-grandchildren.