William H. Dieterich Democratic Scott W. Lucas Democratic The 1938 United States Senate election in Illinois took place on November 8, 1938.

[1] Incumbent first-term Democrat William H. Dieterich retired.

Fellow Democrat Scott W. Lucas was elected to succeed him.

The primaries and general election coincided with those for House and those for state elections.

[1] Primaries were held April 12, 1938.