Abstract: Balance shaft for a piston engine comprises a bearing journal, on which the balance shaft is supported, a gear section, on which a gear is connected in a rotation-locked manner thereto via a press fit or another shaft-hub-connection, and an unbalanced section having an integrally connected unbalanced mass or an unbalanced mass fastened on this unbalanced section using machine elements or via another shaft-hub connection. The balance shaft can alternately comprise steel or cast iron material in the case of a friction mounting and its bearing journals can alternately be implemented as hardened or also unhardened. If the balance shaft is mounted in roller bearings and if the roller bodies have direct contact with the bearing surface, it is implemented in a suitable steel and the bearing journals are hardened. The gear comprises nodular cast iron and is not hardened.