Olof Björnsson (ca 970 - 975), was a semi-legendary Swedish king, who according to Hervarar saga and the Styrbjarnar þáttr Svíakappa ruled together with his brother Eric the Victorious. He was the father of Styrbjörn Starke, and he died of poison during a meal. Instead of proclaiming his son Styrbjörn co-ruler, Eric proclaimed his own unborn child co-ruler on condition that it was a son. It was a son who became Olof of Sweden.