Harald Sigfrid Alexander Julin (27 March 1890 – 31 July 1967) was a Swedish swimmer and water polo player who competed at the 1906, 1908, 1912 and 1920 Olympics.
In 100 m freestyle swimming he won a bronze medal in 1908, and failed to reach the finals in 1906 and 1912; he finished fifth in the 4×250 m freestyle relay in 1906.
In water polo he won bronze medals in 1908 and 1920 and a silver at the 1912 Summer Olympics in his native Stockholm.
His sons Ã…ke and Rolf also became Olympic water polo players.Julle came from a rich family.
Besides water sports he was a fan of motor racing, working as a secretary of the Royal Automobile Club and helping organize several racing events.