John Camillus Lehr (November 18, 1878 – February 17, 1958) was a politician from the U.S. state of Michigan.

In 1932, Lehr defeated seven-term Republican Earl C. Michener to be elected as a Democrat from Michigan's 2nd congressional district to the 73rd United States Congress, serving from March 4, 1933 to January 3, 1935.

Lehr was a delegate to the 1936 Democratic National Convention and was a member of the Monroe Port Commission from 1936 to 1942.

On July 2, 1936, he was appointed by President Franklin D. Roosevelt to be United States Attorney for the Eastern District of Michigan and served in that position until September 2, 1947.

He resigned to devote his time as head of a fraternal beneficiary association in Detroit (The Maccabees), and was succeeded by his chief assistant Thomas P.