The invention relates to the technical field of preparation devices, and discloses a powder coating blending device for paint spraying. The device comprises a fixed box, supporting legs are fixedly connected to four corners of the outer box bottom of the fixed box, a rotating mechanism is connected into the fixed box, the top of the fixed box fixedly communicates with a feeding pipe, the rotatingmechanism comprises a driving motor, a rotating shaft, a rotating box, a driving gear, a supporting rod, a driven gear, an inner gear ring and a plurality of rotating rods, the driving motor is fixedly connected to the inner box bottom of the fixed box, the rotating shaft is connected to the output end of the driving motor through a coupler, the rotating box is rotationally connected to the driving motor through a first bearing, and the rotating box is connected to the fixed box through a rolling mechanism. According to the blending device for the powder coating for paint spraying, the rotating directions of the rotating box and the rotating shaft are opposite, meanwhile, the rotating rod drives the stirring rod to rotate when rotating around the rotating shaft, the vertical stirring effect is achieved, the stirring effect is good, raw materials are stirred more uniformly, and the efficiency is high.