A steel piston with a piston upper part (12) with combustion chamber recess (11) and ring wall (5), and with a piston lower part (13) with piston body or piston skirt and with connecting rod bearing (8) for internal combustion engines with cylinder crankcases made of lightweight metal alloys, with at least the piston lower part consisting of a steel alloy which has a coefficient of thermal expansion in the range from 13 to 20×10−6 1/K.