A motor-driven compressor includes a compression mechanism, an electric motor, a compressor housing, a conductive member, a terminal base, an insulating member, a connection terminal, a wire assembly, a terminal housing, first and second holes formed through the terminal housing and first and second seal members. The conductive member extends from the inside to the outside of the compressor housing and connected electrically to the connection terminal at a terminal connection. The wire assembly has a core wire connecting electrically between the connecting terminal and the electric motor, and an insulator covering the core wire. The terminal housing disposed in the compressor housing covers the terminal connection. The wire assembly has an insulating tube covering the insulator, wherein both ends of the insulating tube are opened for communicating with the inside and the outside of the terminal housing through a clearance formed between the insulating tube and the insulator.