John De Hart (July 25, 1727 – June 1, 1795) was an American lawyer, jurist, and politician from Elizabeth, New Jersey.
De Hart attended the convention and served on the committee that drafted the New Jersey State Constitution in June.
He was appointed to serve on the New Jersey Supreme Court on September 4, 1776, but also made a living practicing law.
De Hart's last act of public service was as Mayor of Elizabeth, New Jersey (then Elizabethtown).
The home that he built in 1766 and lived in for 29 years was called the De Hart House and stood at the intersection of Rahway Avenue and Cherry Street in Elizabeth.