Frank Hiscock (September 6, 1834 – June 18, 1914) was an American lawyer and politician who served as both a U.S. Representative and a U.S.

In addition to practicing law, Hiscock became involved in politics, initially as an anti-slavery Democrat, and then as a member of the Free Soil Party.

He was a member of the State constitutional convention in 1867, elected to fill the vacancy caused by the death of his brother.

He was reelected in 1886 for the term starting March 4, 1887, but resigned in order to accept the U.S. Senate seat to which he had been elected in January, 1887.

Hiscock was elected to the United States Senate by the New York State Legislature, defeating incumbent Warner Miller and Levi P. Morton in the Republican caucus and Democrat Smith M. Weed in the vote of the full legislature.