A motor control device includes a current command calculation unit configured to calculate a current command value for driving a motor, a current detection unit configured to detect a value of a current that flows through a power line of the motor, a current deviation calculation unit configured to calculate a current deviation, which is a difference between the current command value and the detected current value, a voltage command calculation unit configured to calculate a voltage command value applied to the motor based on the current deviation, a filter processing unit configured to calculate data by filtering the current deviation, the absolute value of the current deviation, or the power of the current deviation and to output the data as index data, and a power line breakage detection unit configured to detect a breakage of the power line based on the index data.