John Hamilton Gray, QC (1814 – June 5, 1889) was a politician in the Province of New Brunswick, Canada, a jurist, and one of the Fathers of Confederation.

Gray was elected to the Legislative Assembly of New Brunswick as a supporter of the Colonial Association's platform of reforms in opposition to the Compact government.

In 1855, Lieutenant-Governor John Manners-Sutton dismissed the Reform government over its attempt to institute prohibition and asked Gray to form an administration.

After 1860, Gray drifted away from his fellow Conservatives and became supportive of Samuel Leonard Tilley's Liberal government but was defeated in the 1861 election for his efforts.

Out of elected politics, Gray returned to his practice as a lawyer and was appointed to an inquiry board on the land question in Prince Edward Island.

Gray became an active supporter of Canadian Confederation and joined Tilley's new Liberal-Conservative Party returning to the legislature in a by-election in 1864.

Gray served as a delegate to the Charlottetown Conference only to return to New Brunswick to face growing hostility to the confederation project and lost his seat in the 1865 election that brought the Anti-Confederation Party to power.