An insulation inspection device for accurately inspecting films of wires for an insulation state in a short time before the wires are assembled into a core of an armature in a rotating electric machine, a power supply unit includes a first terminal and a second terminal. A support member supports a plurality of wires covered with films before the wires are assembled into a core of an armature in a rotating electric machine, and the support member is electrically connected to the first terminal. Areas of ends of a plurality of the wires from which areas the films are peeled off are installed on an installation base, and the installation base is electrically connected to the second terminal. A discharge detection unit detects discharge occurring between the support member and each of the wires when the power supply unit applies a voltage to the first terminal or the second terminal.