John Catlin (October 13, 1803 – August 4, 1874) was an American lawyer, politician, railroad executive, and Wisconsin pioneer.

In 1836, he moved to Mineral Point in Wisconsin Territory, where he helped set up a bank.

Catlin was appointed the Secretary of Wisconsin Territory by President James Polk, and served from February 24, 1846, to March 3, 1849.

[6] As acting governor, Catlin went to the present-day city of Stillwater, Minnesota, where he issued a proclamation for a special election for the delegate from the Wisconsin Territory.

[10][page needed] He married Clarissa Bristol on September 19, 1843, and they had one child, Lucia.