Henry Dundas Trotter (1802–1859) was a Scottish officer of the Royal Navy, who reached the rank of rear-admiral.
The third son of Alexander Trotter of Dreghorn, near Edinburgh, he was born on 19 September 1802. He entered the Royal Naval College at Portsmouth in 1815.
In February 1818 joined the Ister at Leith. From her in May he was sent to the Eden of 26 guns, going out to the East Indies, and in her during 1819 taking part in the expedition against the pirates of the Persian Gulf, under Captain Francis Augustus Collier. In March 1821 he was moved to the Leander, flagship of Sir Henry Blackwood, by whom he was appointed acting lieutenant. On arriving in England the commission was confirmed, dating from 9 January 1823. He was then appointed to the Hussar, going out to the West Indies, and was reported by her captain, George Harris, for his conduct in the capture of pirates at the Isle of Pines. He afterwards served in the Bellette and Rattlesnake, and on 20 February 1826 was made commander into the Britomart sloop.
In July 1830 he commissioned the Curlew for service on the west coast of Africa, where he was for the most part senior officer, the commander-in-chief remaining at the Cape of Good Hope. In May 1833, at Prince's Island in the Gulf of Guinea, he had intelligence of an act of piracy committed on an American brig, the Mexican, the previous September, by a large schooner identified as the Panda, a Spanish slaver from Havana, and then on the coast. It was commanded by Pedro Gibert. On 4 June he seized the Panda in the Nazareth River, but the crew escaped to the shore. After a hunt of several months, he succeeded in capturing most of them, and took possession of the Esperanza, a Portuguese schooner, which had been assisting the fugitives. The prisoners and the Esperanza he took to England. The prisoners were sent over to Salem, Massachusetts; the brig they had plundered was then in harbour, and most of them were hanged; Trotter received the thanks of the American government. Against the Esperanza there was no legal evidence; her owners instituted a prosecution against Trotter, and Lord Palmerston, then foreign secretary, agreed that the schooner should be returned to Lisbon. Trotter was called on to fit her out at his own expense. At Plymouth, however, the captains of the ships there sent parties of men who completed her refit free of cost to Trotter; and the Admiralty promoted him to post rank on 16 September 1835.