The invention discloses a stemming forming machine, and relates to the technical field of coal mine equipment. The stemming forming machine comprises a pre-crushing main body and a mixing forming mainbody arranged at the bottom of the pre-crushing main body and communicating with the pre-crushing main body, the pre-crushing main body is internally provided with a first crushing roller and a firstcrushing roller which are arranged in a matched mode, the bottom of the pre-crushing main body is in communication with the upper end of the mixing forming main body through a communication port, a liquid spraying plate is further arranged at the upper end of the interior of the mixing forming main body, a liquid spraying plate is connected to a liquid inlet pipe, a rotating shaft is arranged onthe mixing forming main body and penetrates through the mixing forming main body, a spiral reamer is arranged on the rotating shaft, the right end of the spiral reamer is arranged inside the forming section on the right side of the mixing forming main body, a forming nozzle is assembled on the forming section, and the mixing forming main body is fixedly arranged on a base. The stemming forming machine is good in forming effect, high in raw material utilization rate, simple in structure and low in labor intensity.