William R. Simpson Jr., 74, a retired official of the National Capital Housing Authority and lifelong resident of the Washington area, died of cardiac arrest Saturday at Brooke Grove nursing home in Olney.

Mr. Simpson worked for the Housing Authority from 1943 until retiring in 1966. During his last 15 years with the agency, he was its general counsel and deputy executive director.

He was a member of the Marvin United Methodist Church in Silver Spring for the past 42 years. He was a past president of the Silver Spring Lions Club and was a Lions Club deputy district governor in 1949 and 1950.

Mr. Simpson was born in Washington and had made his home in Silver Spring since 1939. He was a graduate of the old Central High School and National University and its law school. He earned a master's degree in patent law at National in 1937.

His hobbies included fishing and woodworking. During his youth he was a left-handed sandlot baseball pitcher who was known as "Wee Willie" Simpson.

Mr. Simpson was a member of the Federal Bar Association and the National Lawyers Club.

Survivors include his wife, the former Helen Louis Browning, of Silver Spring; a son, William R. III, of Clearwater, Fla.; a daughter, Nancy Richards of Silver Spring; nine grandchildren and two great-grandchildren.