Sophus Weidemann (1836 – 1894) was a Norwegian engineer and industrialist who contributed to the development of the shipping industry in Norway. From 1864 to 1871 he was manager of the workshop Fabrikken in Trondheim, the later ship building company Trondhjems mekaniske Værksted. He was the grandson of civil servant Lauritz Weidemann, and among his uncles was psychiatrist Herman Wedel Major.[1][2]