The 1857 United States Senate election in New York was held on February 3, 1857 by the New York State Legislature. Incumbent Whig Senator Hamilton Fish did not stand for re-election. The seat was won by Preston King, a former U.S. Representative and member of the newly-formed Republican Party. King was the first Republican elected to represent New York, although William H. Seward had joined the party after being elected as a Whig in 1855.

Preston King was an American attorney and politician who represented New York in the United States Senate from 1857 to 1863. King also represented the North Country in the U.S. House of Representatives for three terms and represented his native St. Lawrence County in the New York State Assembly for four terms. King entered politics as an ally of Martin Van Buren and was a lifelong opponent of slavery as a member of the Democratic, Free Soil, and Republican parties.