A steering control device comprising: a plurality of control systems configured to control driving of a motor by switching between a plurality of drive modes including a cooperative drive mode and an independent drive mode, wherein each of the control systems includes a control unit configured to calculate a command value for controlling the motor, wherein the control systems are configured to control the driving of the motor based on the command value calculated by the control unit of one control system of the control systems when the cooperative drive mode is performed, wherein the control systems are configured to control the driving of the motor based on the command values respectively calculated by the control units of the control systems when the independent drive mode is performed, wherein the control systems are configured to switch the drive mode to the cooperative drive mode when the command values calculated by the control units of the control systems are not different from each other and to switch the drive mode to the independent drive mode when the command values calculated by the control units of the control systems are different from each other, characterized in that the control systems are configured to gradually limit the command values respectively calculated by the control units of the control systems when a start switch of a vehicle has been turned off, and in that the control systems are configured to switch the drive mode to the independent drive mode regardless of whether the command values calculated by the control units of the control systems are different from each other when the start switch has been turned off while the vehicle is traveling. a plurality of control systems configured to control driving of a motor by switching between a plurality of drive modes including a cooperative drive mode and an independent drive mode, wherein each of the control systems includes a control unit configured to calculate a command value for controlling the motor, wherein the control systems are configured to control the driving of the motor based on the command value calculated by the control unit of one control system of the control systems when the cooperative drive mode is performed, wherein the control systems are configured to control the driving of the motor based on the command values respectively calculated by the control units of the control systems when the independent drive mode is performed, wherein the control systems are configured to switch the drive mode to the cooperative drive mode when the command values calculated by the control units of the control systems are not different from each other and to switch the drive mode to the independent drive mode when the command values calculated by the control units of the control systems are different from each other, characterized in that the control systems are configured to gradually limit the command values respectively calculated by the control units of the control systems when a start switch of a vehicle has been turned off, and in that the control systems are configured to switch the drive mode to the independent drive mode regardless of whether the command values calculated by the control units of the control systems are different from each other when the start switch has been turned off while the vehicle is traveling.