Dewey William Johnson (March 14, 1899 – September 18, 1941) was an American lawyer and politician from Minnesota. Johnson was born in Minneapolis and attended the local public schools, followed by the University of Minnesota and William Mitchell College of Law (then the YMCA Law School).

Dewey Johnson
Member of the U.S. House of Representatives from Minnesota's 5th district
In office January 3, 1937 – January 3, 1939
Preceded by	Theodore Christianson
Succeeded by	Oscar Youngdahl
Personal details
Born	(1899-03-14)March 14, 1899 Minneapolis, Minnesota, U.S.
Died	September 18, 1941(1941-09-18) (aged 42) Minneapolis, Minnesota, U.S
Political party	Farmer–Labor Party
Education	University of Minnesota YMCA Law School

After graduation from law school, he began work in the insurance business. He was elected to the Minnesota House of Representatives in 1929 and served until 1935. In 1934, he had been an unsuccessful candidate for election to the 74th congress. After his six-year stint in the Minnesota House, Johnson served as Deputy Commissioner of Insurance and as the state Fire Marshal. A second Congressional run in 1936 was successful; Johnson served as a member of the Farmer-Labor Party in the 75th congress, (January 3, 1937–January 3, 1939). However, in 1938 he was defeated for re-election by Oscar Youngdahl, a Republican, and when he again ran in 1940 against Youngdahl he was again defeated.

Johnson resumed his insurance practice in Minneapolis and also operated a retail radio sales business. He died in Minneapolis in 1941.