Sitalces (Sitalkes) (/sɪˈtælˌsiːz/; Ancient Greek: Σιτάλκης; reigned 431–424 BC) was one of the kings of the Thracian Odrysian state. The Suda called him Sitalcus (Σίταλκος).
He was the son of Teres I, and on the sudden death of his father in 431 BC succeeded to the throne. Sitalces enlarged his kingdom by successful wars, and it soon comprised the whole territory from Abdera in the south to the mouths of the Danube in the north, and from the Black Sea in the east to the sources of the Struma in the west.