Isaac Van Wart, sometimes spelled Van Wert, (1760-May 23, 1828) was a soldier in the American Revolutionary War who was one of three men who captured the spy John André, the others being David Williams and John Paulding.

He was born in Greenburg, New York and was a farmer in Westchester County, New York.

André was on a mission carrying secret papers from Benedict Arnold when he was stopped by an armed patrol consisting of John Paulding, David Williams, and Van Wart. Believing them to be Tories, André told them he was a British officer who must not be detained, when, to his surprise, they said they were Americans, and that he was their prisoner. He then told them that he was an American officer, and showed them his passport. But the suspicions of his captors were now aroused, and they searched him and found Arnold's papers in his stocking. André offered them his horse, watch, and 100 guineas, if they would let him go, but they were not to be bribed.

Gen. Washington sought out the three men who, "leaning only on their virtue and an honest sense of their duty," could not be tempted by gold. On his recommendation the United States Congress gave each of the captors a pension of $200 a year and a silver medal, known as the Fidelity Medallion. Van Wart was also honored by an 1853 monument erected at the place of the capture. Van Wert County, Ohio is named for him and the other captors are also honored with Ohio counties.