An electric power steering device, comprising: a control unit; and an electric motor, the control unit being configured to control drive of the electric motor and being arranged coaxially with an output shaft of the electric motor on a side opposite to an output side of the output shaft, the control unit and the electric motor being integrated with each other through connection between a motor control terminal (2c, 2e) of the control unit and a winding terminal (2d, 2f) of the electric motor, the control unit comprising: a case; a connector assembly, which is provided on an outer side of the case; a heat sink, which is configured to close an opening portion of the case to form a space in cooperation with the case; a power module, which is placed on the heat sink within the space, and is configured to supply power to the electric motor; a holder, which is configured to press the power module against the heat sink to bring the power module in close contact with the heat sink, and to position the power module; and a control board, which is provided so as to be separate from the holder, the control board having mounted thereon a central processing unit configured to control drive of the electric motor, the power module comprising a plurality of terminals including the motor control terminal (2c, 2e) and a power supply terminal (4c, 4d) connected to a power supply, each having a distal end portion being oriented toward the control board, the holder having holes through which the plurality of terminals pass, the terminals each having the distal end portion to be connected to the control board, the winding terminal (2d, 2f) having a distal end portion to be connected to the distal end portion of the motor control terminal (2c, 2e), the control unit further comprising a junction terminal, the junction terminal and the power supply terminal (4c, 4d) each having a distal end portion extending from the control board toward the connector assembly being respectively connected to connector terminals of the connector assembly. a control unit; and an electric motor, the control unit being configured to control drive of the electric motor and being arranged coaxially with an output shaft of the electric motor on a side opposite to an output side of the output shaft, the control unit and the electric motor being integrated with each other through connection between a motor control terminal (2c, 2e) of the control unit and a winding terminal (2d, 2f) of the electric motor, the control unit comprising: a case; a connector assembly, which is provided on an outer side of the case; a heat sink, which is configured to close an opening portion of the case to form a space in cooperation with the case; a power module, which is placed on the heat sink within the space, and is configured to supply power to the electric motor; a holder, which is configured to press the power module against the heat sink to bring the power module in close contact with the heat sink, and to position the power module; and a control board, which is provided so as to be separate from the holder, the control board having mounted thereon a central processing unit configured to control drive of the electric motor, a case; a connector assembly, which is provided on an outer side of the case; a heat sink, which is configured to close an opening portion of the case to form a space in cooperation with the case; a power module, which is placed on the heat sink within the space, and is configured to supply power to the electric motor; a holder, which is configured to press the power module against the heat sink to bring the power module in close contact with the heat sink, and to position the power module; and a control board, which is provided so as to be separate from the holder, the control board having mounted thereon a central processing unit configured to control drive of the electric motor, the power module comprising a plurality of terminals including the motor control terminal (2c, 2e) and a power supply terminal (4c, 4d) connected to a power supply, each having a distal end portion being oriented toward the control board, the holder having holes through which the plurality of terminals pass, the terminals each having the distal end portion to be connected to the control board, the winding terminal (2d, 2f) having a distal end portion to be connected to the distal end portion of the motor control terminal (2c, 2e), the control unit further comprising a junction terminal, the junction terminal and the power supply terminal (4c, 4d) each having a distal end portion extending from the control board toward the connector assembly being respectively connected to connector terminals of the connector assembly.