This flexible printed wiring board comprises: a base film having insulating properties; and a conductive pattern laminated on one surface side of this base film. The conductive pattern constitutes part of a circuit. The flexible printed wiring board has at least one fuse having a smaller cross-sectional area than the other part of the circuit and comprises at least one opening on at least either the left or right side of the fuse section, in the planar view, said opening piercing the front and rear surfaces.