James Merrill Cook (November 19, 1807 in Ballston, Saratoga County, New York – April 12, 1868 in Saratoga, New York) was an American businessman, banker and politician.

At the state election in November 1851, he was elected New York State Treasurer on the Whig ticket by a margin of only 228 votes (200,693 for Cook; 200,465 for Welch), and took office on January 1, 1852.

He was New York State Comptroller from 1854 to 1855, defeated for re-election in 1855 by the American Party candidate Lorenzo Burrows.

Their daughter, Catherine Phillips Cook married George Sherman Batcheller.

Cook is buried in the Ballston Spa Village Cemetery.