Charles Lewis Gerlach (September 14, 1895 – May 5, 1947) was an American businessman and politician who served five terms as a Republican member of the U.S. House of Representatives from Pennsylvania from 1939 until his death in 1947.

In 1914, he moved to Allentown, Pennsylvania, where he became the organizer, and later president, of a fuel and heating supply company.

[2] A Republican State committeeman in 1936 and 1937, he was elected to the 76th Congress in 1938, and served until his 1947 death in Allentown.

A rugged Isolationist before Pearl Harbor, who voted only for purely defensive measures, such as conscription and arming of United States ships.

Though he opposed the original Lend-Lease, he favoured its continuation, but would be difficult to say exactly where he stands on the larger questions of post-war American policy.On May 5, 1947, while still serving in Congress, Gerlach died in Allentown, Pennsylvania, at age 51.