An electric compressor has a compressor housing, a compression mechanism, an electric motor, an accommodating portion and a motor drive circuit. The compressor housing has a circumferential wall and a central axis. The compression mechanism is arranged in the compressor housing for compressing fluid. The electric motor is operatively connected to the compression mechanism for driving the compression mechanism. The accommodating portion is provided on an outer surface of the compressor housing and defines an accommodating space. The inner surface of the accommodating space includes a bottom surface and a side surface. The bottom surface is defined as a radially inward surface of the inner surface relative to the central axis. The side surface surrounds a periphery of the bottom surface. The bottom and side surfaces are defined by the compressor housing. The motor drive circuit is arranged in the accommodating space for driving the electric motor.