Ivar Throndsen (March 29, 1853 – January 18, 1932) was a Norwegian engraver.
Throndsen was born in Nes, Akershus. He became an apprentice to the goldsmith Jacob Tostrup in Christiania (now Oslo) in 1870, and at the same time studied at the Norwegian National Academy of Craft and Art Industry under the sculptor Julius Middelthun. He received a job at the Royal Mint in Kongsberg in 1879 and, after finishing his studies, started working there in 1880. He produced nearly 500 medals, tokens, and badges during his career. Throndsen died in Kongsberg. His work was cataloged by Ragnar Støren and Hans Holst in 1937.