Henry Clay Ide (September 18, 1844 – June 13, 1921) was a U.S. judge, colonial commissioner, ambassador, and Governor-General of the Philippines.

Ide was born in Barnet, Vermont, on September 18, 1844, a son of Jacob and Lodoiska (Knights) Ide. He graduated from Dartmouth College in 1866, where he was named valedictorian. He studied law, first with Benjamin H. Steele, and later with Jonathan Ross, and was admitted to the bar in 1870. He practiced law in St. Johnsbury, Vermont from until 1891, and was the partner of Wendell Phillips Stafford. Among the prospective attorneys who studied law in their office was William H. Taylor, who later served as an Associate Justice of the Vermont Supreme Court.

A Republican, Ide was State's Attorney for Caledonia County from 1876 to 1878. He was then a member of the Vermont State Senate from 1882 to 1885.

President Benjamin Harrison appointed Ide Presidential Commissioner to Samoa in 1891. The formal title of the post was American Land Commissioner in Samoa, one of three representatives (of the United States, Germany, and Great Britain) responsible for adjudicating land claims by foreigners in the islands, as provided for in the Treaty of Berlin (1889). Ide reached Apia on May 16, 1891, but only held the office for six months, until he resigned because of a serious illness in his family and left the islands on November 12, 1891. Robert Louis Stevenson wrote to him two days beforehand, saying "I hear with great regret of your departure. They say there are as good fish in the sea as ever came out of it, but I doubt if they will come to our hook. It is not only that you have shown so much capacity, moderation, tact, and temper; but you have had the talent to make these gifts recognized and appreciated among our very captious population. For my part, I always thought your presence the best thing that the treaty had brought us."

Ide returned to the islands in 1893 as Chief Justice, another position provided for by the Treaty of Berlin. He accepted the appointment in August, and sailed for the islands two months later. As Chief Justice, Ide presided over trials of both native Samoans and foreign nationals of the three Treaty of Berlin signatories. He also had the power to recommend criminal and taxation legislation to the government of Samoa. He resigned in 1896, but there was a delay in the arrival of his successor, requiring him to continue in office until 1897. At his departure, the Samoa Weekly Herald editorialized that Ide had been a just and able judge. Similarly, King Malietoa told Ide that "You will not be forgotten in Samoa, you will be remembered as the good Chief Justice who knew our ways and laws and customs and who was kind to us".

Ide was succeeded as Land Commissioner and Chief Justice by William Lea Chambers.

Ide was one of the Commissioners of the Taft Commission, appointed in 1900. Like the other Commissioners, he arrived in the Philippines in June of that year, and assumed official legislative power on September 1, 1900.

In 1901, Ide and the other commissioners gained executive power when they were appointed to the cabinet of territorial Governor William Howard Taft. Ide was appointed Secretary of Finance and Justice, and served until 1904.