A drum washing machine, comprising: an outer tub disposed in a housing; a drum disposed in the outer tub and being rotatable by using a horizontal axis or an inclination axis inclined relative to a horizontal direction as a center; a rotating body disposed in the drum and provided with a protruding part in contact with washings on a surface; and a driving part configured to rotate the drum and the rotating body, wherein the driving part comprises: a driving motor; a first belt wheel fixed to a rotating shaft of the drum; a second belt wheel fixed to a rotating shaft of the rotating body; a first motor belt wheel fixed to a motor shaft of the driving motor and connected with the first belt wheel via a first transmission belt; a second motor belt wheel connected with the second belt wheel via a second transmission belt;: a clutch mechanism part for switching a driving form of the driving part between a first driving form, in which the drum and the rotating body rotate along with rotation of the driving motor through connection of the motor shaft and the second motor belt wheel in such a manner that the rotation of the motor shaft is capable of being transmitted to the second motor belt wheel, and a second driving form; characterized in that in the first driving form the drum and the rotating body rotate at different rotating speeds and that in the second driving form the motor shaft is disconnected from the second motor belt wheel in such a manner that the rotation of the motor shaft is not transmitted to the second motor belt wheel. an outer tub disposed in a housing; a drum disposed in the outer tub and being rotatable by using a horizontal axis or an inclination axis inclined relative to a horizontal direction as a center; a rotating body disposed in the drum and provided with a protruding part in contact with washings on a surface; and a driving part configured to rotate the drum and the rotating body, wherein the driving part comprises: a driving motor; a first belt wheel fixed to a rotating shaft of the drum; a second belt wheel fixed to a rotating shaft of the rotating body; a first motor belt wheel fixed to a motor shaft of the driving motor and connected with the first belt wheel via a first transmission belt; a second motor belt wheel connected with the second belt wheel via a second transmission belt;: a clutch mechanism part for switching a driving form of the driving part between a first driving form, in which the drum and the rotating body rotate along with rotation of the driving motor through connection of the motor shaft and the second motor belt wheel in such a manner that the rotation of the motor shaft is capable of being transmitted to the second motor belt wheel, and a second driving form; characterized in that in the first driving form the drum and the rotating body rotate at different rotating speeds and that in the second driving form the motor shaft is disconnected from the second motor belt wheel in such a manner that the rotation of the motor shaft is not transmitted to the second motor belt wheel. a driving motor; a first belt wheel fixed to a rotating shaft of the drum; a second belt wheel fixed to a rotating shaft of the rotating body; a first motor belt wheel fixed to a motor shaft of the driving motor and connected with the first belt wheel via a first transmission belt; a second motor belt wheel connected with the second belt wheel via a second transmission belt;: a clutch mechanism part for switching a driving form of the driving part between a first driving form, in which the drum and the rotating body rotate along with rotation of the driving motor through connection of the motor shaft and the second motor belt wheel in such a manner that the rotation of the motor shaft is capable of being transmitted to the second motor belt wheel, and a second driving form; characterized in that in the first driving form the drum and the rotating body rotate at different rotating speeds and that in the second driving form the motor shaft is disconnected from the second motor belt wheel in such a manner that the rotation of the motor shaft is not transmitted to the second motor belt wheel. a clutch mechanism part for switching a driving form of the driving part between a first driving form, in which the drum and the rotating body rotate along with rotation of the driving motor through connection of the motor shaft and the second motor belt wheel in such a manner that the rotation of the motor shaft is capable of being transmitted to the second motor belt wheel, and a second driving form; characterized in that in the first driving form the drum and the rotating body rotate at different rotating speeds and that in the second driving form the motor shaft is disconnected from the second motor belt wheel in such a manner that the rotation of the motor shaft is not transmitted to the second motor belt wheel.