He was the eldest son of Konrad V Kantner, Duke of Oleśnica by his wife Margareta.

Konrad IX obtain Oleśnica, Koźle and half of Bytom.

During the wars between Bohemia and Hungary, he initially supported King George of Poděbrady and paid homage to him with his brother Konrad X in 1459 in exchange for the confirmation of the possession of their father's Duchy; however, when the Hungarian troops entered in Silesia, Konrad IX and Konrad X repudied his alliance with Bohemia and paid homage to King Matthias Corvinus.

In 1459 Konrad IX buy the half of the Duchy of Bytom who belonged to the Cieszyn branch[1] by the amount of 1,700 fines.

They had one daughter: On his death, Konrad IX was succeeded by his brother in all his lands except Oleśnica and Bierutów, who were leave to his wife Margareta as her dower.