To provide an on-load tap changer which can be made compact, be arranged compactly, easily and inexpensively and can increase reliability and economy by increasing a cooling efficiency for a current limiting resistor while securing a mechanical strength.

A current limiting resistor 3a is formed by bending a plate-shaped resistor having a groove 23a provided therein to a continuous S shape. The groove 23a is made up of grooves cut in the upper edge of the current limiting resistor 3a and extended to its lower edge and grooves cut in the lower edge of the current limiting resistor 3a and extended to its upper edge, and two types of grooves are alternately provided to be parallel to each other.