The invention belongs to the technical field of PVC pipes, and particularly relates to a raw material stirring tank for PVC pipe machining. A tank body is included. A stirring shaft is arranged at themiddle portion in the tank body and provided with a plurality of fixedly-connected stirring rods. A stirring motor is arranged at the center position of the bottom of the tank body. An output shaft is arranged at the output end of the stirring motor and movably penetrates through the bottom of the tank body. The bottom of the stirring shaft is provided with a connecting groove movably connected with the output shaft. The part, located in the tank body, of the output shaft is provided with a plurality of limiting blocks, and the side wall of the connecting groove is provided with a plurality of limiting grooves matched with the limiting blocks. The outer side wall of the upper end portion of the stirring shaft is provided with a reciprocating thread, the part, located on the outer side ofthe reciprocating thread, of the stirring shaft is provided with a connecting block connected with the reciprocating thread, the outer side of the connecting block is provided with a plurality of fixing rods, and the fixing rods are fixedly connected with the inner wall of the tank body. The stirring efficiency of raw materials in the tank body is improved, stirring is more thorough, and the subsequent product quality is improved.