Abstract: The present invention provides a single-frame impeller of a wind turbine generator set. The impeller includes blades and a blade adjusting device. The blade adjusting device comprises a blade adjusting chamber to which the blades are connected, a motor and an adjusting mechanism. The adjusting mechanism comprises transmission mechanism, adjusting frame, rotating arm and connecting rods. Transmission mechanism comprises swinging arm, a positioning shaft, a main drive arm and a push-pull rod. The adjusting frame is assembled onto blade adjusting chamber; the rotating arms are fixed on the blade shafts and the connecting rods, and the other end of each connecting rod is hinged with the adjusting frame; two ends of the positioning shaft are installed on the fixed seat; swinging arm is fixed at positioning shaft and is hinged with main drive arm, and the main drive arm is connected with the motor.