A motor control device configured to control a motor, comprising: an inverter part configured to convert direct current into alternate current in response to a motor drive command; a gate driving circuit configured to drive the inverter part; a PWM generation circuit configured to generate a PWM signal applied to the gate driving circuit; and at least one gate buffer (12, 22; 112, 122) disposed between the gate driving circuit and the PWM generation circuit, characterized in that: the motor control device comprises a control part configured to apply a test signal (DPOUT) to the gate buffer (12, 22; 112, 122) to determine abnormality of the gate buffer (12, 22; 112, 122), the gate buffer (12, 22; 112, 122) comprises: a diagnosis signal input part configured to input the test signal (DPOUT); and a diagnosis signal output part configured to output a diagnosis signal (DPIN1, DPIN2) based on the test signal (DPOUT) inputted by the diagnosis signal input part, and the control part comprises a diagnosis part configured to determine that the abnormality has occurred in the gate buffer (12, 22; 112, 122) when a state of a switch control signal (BBON1, BBON2) and a state of the diagnosis signal (DPIN1, DPIN2) do not correspond to each other, and the abnormality has not occurred in the gate buffer (12, 22; 112, 122) when the state of the switch control signal (BBON1, BBON2) and the state of the diagnosis signal (DPIN1, DPIN2) correspond to each other, based on the switch control signal (BBON1, BBON2) for switching a conduction state or a blocking state of the PWM signal at the gate buffer (12, 22; 112, 122) and the diagnosis signal (DPIN1, DPIN2). an inverter part configured to convert direct current into alternate current in response to a motor drive command; a gate driving circuit configured to drive the inverter part; a PWM generation circuit configured to generate a PWM signal applied to the gate driving circuit; and at least one gate buffer (12, 22; 112, 122) disposed between the gate driving circuit and the PWM generation circuit, characterized in that: the motor control device comprises a control part configured to apply a test signal (DPOUT) to the gate buffer (12, 22; 112, 122) to determine abnormality of the gate buffer (12, 22; 112, 122), the gate buffer (12, 22; 112, 122) comprises: a diagnosis signal input part configured to input the test signal (DPOUT); and a diagnosis signal output part configured to output a diagnosis signal (DPIN1, DPIN2) based on the test signal (DPOUT) inputted by the diagnosis signal input part, and the control part comprises a diagnosis part configured to determine that the abnormality has occurred in the gate buffer (12, 22; 112, 122) when a state of a switch control signal (BBON1, BBON2) and a state of the diagnosis signal (DPIN1, DPIN2) do not correspond to each other, and the abnormality has not occurred in the gate buffer (12, 22; 112, 122) when the state of the switch control signal (BBON1, BBON2) and the state of the diagnosis signal (DPIN1, DPIN2) correspond to each other, based on the switch control signal (BBON1, BBON2) for switching a conduction state or a blocking state of the PWM signal at the gate buffer (12, 22; 112, 122) and the diagnosis signal (DPIN1, DPIN2). the motor control device comprises a control part configured to apply a test signal (DPOUT) to the gate buffer (12, 22; 112, 122) to determine abnormality of the gate buffer (12, 22; 112, 122), the gate buffer (12, 22; 112, 122) comprises: a diagnosis signal input part configured to input the test signal (DPOUT); and a diagnosis signal output part configured to output a diagnosis signal (DPIN1, DPIN2) based on the test signal (DPOUT) inputted by the diagnosis signal input part, and a diagnosis signal input part configured to input the test signal (DPOUT); and a diagnosis signal output part configured to output a diagnosis signal (DPIN1, DPIN2) based on the test signal (DPOUT) inputted by the diagnosis signal input part, and the control part comprises a diagnosis part configured to determine that the abnormality has occurred in the gate buffer (12, 22; 112, 122) when a state of a switch control signal (BBON1, BBON2) and a state of the diagnosis signal (DPIN1, DPIN2) do not correspond to each other, and the abnormality has not occurred in the gate buffer (12, 22; 112, 122) when the state of the switch control signal (BBON1, BBON2) and the state of the diagnosis signal (DPIN1, DPIN2) correspond to each other, based on the switch control signal (BBON1, BBON2) for switching a conduction state or a blocking state of the PWM signal at the gate buffer (12, 22; 112, 122) and the diagnosis signal (DPIN1, DPIN2).