Sir Martin Beckman (1634/35–1702) was a draughtsman/painter, Swedish-English colonel, chief engineer and master gunner of England.
Beckman was born in , the son of Melcher Beckman and his wife Chistiana van Benningen. He left Sweden around 1645 to serve Charles I during the English Civil War. His brother, also a military engineer serving Charles, was taken prisoner by the parliament forces in 1644, but after some time on bread and water, was released in a poor state of health. In 1653 he joined the royalist exiles at Middelburg, the bearer of important information from England, and died before the Restoration. Martin Beckman in 1660 petitioned Charles II for the place of royal engineer, formerly enjoyed by his brother, and mentioned that he "was ruined and severely injured by an accident at an explosion in the preparation of fireworks to be shown on the water in the king's honour." He was accordingly employed as an engineer, and his skill in laboratory work led to his appointment on 6 June 1661 to the expedition under Edward Montagu, 1st Earl of Sandwich as "firemaster with and in his majesty's fleete".
He sailed from Deptford with the fleet on 13 June in the ship Augustine, and, after a short time at Alicante, proceeded against the pirates of Algiers; but, the enterprise failing, the fleet bore away for Tangiers, of which possession was taken as part of the dowry of Catherine of Braganza on 30 January 1662. A governor and garrison were left there, and the fleet proceeded to Lisbon to escort Queen Catherine to England. Plans of the actions at Algiers were made by Beckman and later engraved. In Tangier, Beckman made plans of the place and proceeded to erect a number of fortifications, mainly outlying fortlets. A plan of Tangiers was sent home before the fleet returned, and Samuel Pepys mentions in his Diary under 28 February 1662, that he presented to the Duke of York from Lord Sandwich "a fine map of Tangiers, done by one Captain Martin Beckman, a Swede, that is with my lord. We stayed looking over it a great while with the duke." This map is in the collection of George III in the British Museum.