A motor drive device is provided which includes: a first drive unit configured to drive a plurality of first motor phases; a second drive unit configured to drive a plurality of second motor phases; a common sensor configured to detect a total current flowing through a phase pair obtained by selecting one phase from the plurality of first motor phases and one phase from the plurality of second motor phases; at least one first motor phase sensor and at least one second motor phase sensor configured to detect each current flowing through each phase not included in the phase pair among the plurality of first motor phases and the plurality of second motor phases, respectively; and a drive control unit configured to control drive amounts of the first drive unit and the second drive unit for the plurality of first motor phases and the plurality of second motor phases.