Siemion

The name Siemion may refer to:

As a surname:
 * Andrew Siemion (born 1980), American astrophysicist
 * Łukasz Siemion (born 1985), Polish rower
 * Wojciech Siemion (1928–2010), Polish stage and film actor

As a given name:
 * Semyon Budyonny (1883–1973), also spelled Siemion Budionnyi, Soviet cavalryman, military commander, and politician
 * Siemion Fajtlowicz (fl. 1967), Polish mathematician