Clarence Duncan Van Zandt (March 21, 1853 – June 17, 1926) was an American businessman and politician who served as the 50th mayor of Rochester, New York from 1922 to 1926.

After receiving an education in the public schools, he was hired as an errand boy for the Lane and Paine Drug Company.

George Aldridge, the boss of the local Republican Party, faced a challenge to his leadership from city council member Chip Bostwick, and recruited Van Zandt to run against him.

[4] Reform groups sought to break the power of the Republican machine during Van Zandt's term.

The Municipal Research Bureau, founded by George Eastman, became increasingly influential in the 1920s and made many policy recommendations.