To provide a cloud prevention glass capable of increasing and decreasing a total heat generation amount of heating wires for preventing cloud provided on a rear part window glass of a vehicle depending on purpose of use and increasing a total heat generation amount electrically when freezing so as to melt ice and snow over the whole heating face of the heating wires for preventing cloud in a short period of time.

This cloud prevention glass for rear part window for the vehicle composed of a plurality of heating wires is constituted such that the heating wires are divided into a plurality of groups of heating wires, and bus bars are provided at both ends of each group of heating wires to connect the groups of heating wires mutually as a series and/or parallel circuit or a circuit in which they are combined by turning on and off selector switches provided appropriately among each group of heating wires and change a total resistance value of conductive wires for heating by turning on and off the selector switches so as to change over a heat generation amount over the whole heating face of the cloud prevention heating wires.