Géza II (Hungarian: II. Géza, Slovak: Gejza) was king of Hungary from 1141 until his death in 1161.

Géza was the son Béla II of Hungary and Serbian Princess Ilona (Jelena). He succeeded his father as King of Hungary in 1141, and because he was still a minor, his maternal uncle, Duke of Hungary, Prince Belos of Rascia served as regent of the Kingdom helped by his sister, Queen Ilona of Hungary. He faced challenges from Boris, the son of King Kálmán's adulterous queen, who disputed his claim to the throne. As an adult, Géza had a reputation as a well-respected king, whose nobles did not dare to scheme against him. The power and valor of his army was also commented upon, and Géza did not hesitate to involve himself in politics. He supported the Welf party against the Hohenstaufens, and defeated Henry II of Austria in battle in 1146. He also supported his brother-in-law, Iziaslav II of Kiev, militarily, and fought a war against the Byzantine Emperor Manuel I Comnenus from 1149 to 1155. After a failed attempt to achieve power in Rascia, Belo? awarded himself the Banate of Croatia in 1142, which he reigned until 1158.

In 1146, Géza married Euphrosyne of Kiev, daughter of Grand Duke Mstislav of Kiev. Their children were:
1. István III (1147-1172)
2. Béla III (1148-1196)
3. Ilona of Hungary (died 1199), married Leopold V, Duke of Austria