John Cotton Mather (November 30, 1813 in Deposit, Delaware County, New York – August 13, 1882 in Watertown, Jefferson County, New York) was an American politician.
In 1853, he was the first person tried by the New York Court for the Trial of Impeachments.
At the New York state election, 1847, he ran for Canal Commissioner on the Democratic and Anti-Rent tickets, but was defeated.
At the New York state election, 1853, he ran for re-election on the Hard ticket, but was defeated by Whig Cornelius Gardinier.
State Senator Francis M. Bixby (born 1828) was his nephew.