Cornelius Gardinier (June 24, 1809 in Fultonville, Montgomery County, New York – October 21, 1892 in Darien, Fairfield County, Connecticut) was an American politician from New York.
Born to Rynier Gardinier and Mary Newkirk, he married Catherine and had at least ten children.
He was Postmaster of Fultonville from 1841 to 1843. In 1853, he ran for Canal Commissioner on the Whig ticket against John C. Mather. He won the election and remained in office from 1854 until 1856.
He died on October 21, 1892, in Darien, Connecticut, at the home of his son-in-law J. H. Taylor.