Wenceslaus III Premyslid (Czech and Slovak: Václav III., German: Wenzel III., Hungarian: Vencel, Polish: Wacław, Croatian: Vjenceslav III, Serbian: Вeнцeслав III, Venceslav III; 6 October 1289 – 4 August 1306) is the King of Hungary (1301–05), King of Bohemia (1305–06) and the king of Poland (1305–06).

Wenceslaus III is the son of Wenceslaus II, King of Bohemia and Poland, and Judith of Habsburg, the daughter of Rudolph I, King of the Romans.

During his short reign, the teenaged king faces the problem of significant internal quarrels in Hungary and in Poland.

Wenceslaus is the last of the male Přemyslid rulers of Bohemia.

His sister Elizabeth marries John of Luxembourg, who is elected King of Bohemia after his death.