The invention provides a cabin cover assembly adjustment device of a wind power generating set. The cabin cover assembly adjustment device comprises a left supporting adjustment apparatus, a right supporting adjustment apparatus, a left motor controller and a right motor controller, wherein the left supporting adjustment apparatus supports and adjusts the left half portion of a cabin cover; the right supporting adjustment apparatus supports and adjusts the right half portion of the cabin cover; the left supporting adjustment apparatus and the right supporting adjustment apparatus each comprises a supporting frame, an X-direction movement mechanism, a Y-direction movement mechanism and a Z-direction movement mechanism, wherein the X-direction movement mechanism comprises an X-direction motor, the Y-direction movement mechanism comprises a Y-direction motor, and the Z-direction movement mechanism comprises a Z-direction motor; the left motor controller is connected with the X-direction motor, the Y-direction motor and the Z-direction motor of the left supporting adjustment apparatus; and the right motor controller is connected with the X-direction motor, the Y-direction motor and theZ-direction motor of the right supporting adjustment apparatus. The cabin cover assembly adjustment device of the wind power generating set has the beneficial effects that the cabin cover can be supported conveniently, the X-direction position, the Y-direction position and the Z-direction position of the cabin cover can be adjusted, automatic control is achieved, the automation degree is high, manual effort is not needed, the labor intensity of manual work is greatly relieved, and the position of the cabin cover is adjusted quite conveniently.