Hejnum is a populated area, a socken (not to be confused with parish), on the Swedish island of Gotland.

[3] It comprises the same area as the administrative Hejnum District, established on 1 January 2016.

[4] Hejnum is situated in the northern inland of Gotland just south of Lake Tingstäde.

Central Hejnum consists of flat farmlands with forest area in the west and east.

[9] One of the most magnificent medieval gate portals on Gotland, is at the Riddare farm in Hejnum.