James W. Wahner (born November 10, 1939) is a retired American government administrator and Democratic politician.

He served 9 years in the Wisconsin State Assembly, representing Milwaukee County, and was majority leader from January 1977 until his resignation in January 1980.

He left the Assembly to serve as Midwest Regional Director of the Federal Emergency Management Agency in the administration of U.S. President Jimmy Carter.

He graduated from Mercer High School and served in the United States Army from 1959 to 1962.

This article about a Democratic Party member of the Wisconsin State Assembly is a stub.