The invention relates to a single-driving system of a washing machine, which comprises a motor, a shell, a clutch mechanism, a driving shaft and a driving shaft sleeve. The driving shaft is rotatably arranged in the driving shaft sleeve, the motor is an outer rotor motor, the shell comprises a lower shell and an upper shell which are fixedly connected, the lower shell is used as a stator retainer of an inner stator, the stator retainer is fixedly connected with the inner stator, the clutch mechanism is located in an inner space, the lower shell and the upper shell are fixedly connected to form the inner space, the clutch mechanism comprises an electromagnetic coil mechanism, a clutch gear ring, a meshing component, an upper matching component and a lower matching component, a mounting plate is used as the upper matching component, the driving shaft located above the stator retainer is fixedly connected with a clutch gear disc, the clutch gear disc is used as the lower matching component, and the clutch gear ring vertically moves along the meshing component and selectively matches with the mounting plate and the clutch gear disc. The single-driving system of the washing machine is fine in clutch performance, low in manufacturing cost and noise, convenient in installation and quite suitable for popularization and application in production.