The invention belongs to the technical field of plastic woven bag producing and processing, and particularly relates to a plastic extruding machine. According to the technical scheme, the plastic extruding machine comprises a horizontally arranged spiral conveyor, a hopper is arranged above the feeding end of the spiral conveyor, and an extruding opening is formed in the discharging end of the spiral conveyor; and an electric heating device is arranged on the outer wall of the spiral conveyor, the middle section of the spiral conveyor is connected with a vacuumizing pipeline, and a filter screen is arranged between the discharging end and the extruding opening of the spiral conveyor. Water vapor in the plastic extruding machine is removed through the vacuumizing pipeline, and bubbles are prevented from being generated in a plastic product. In addition, the filter screen is used for filtering out particle impurities, the plastic purity is improved, and then the surface quality and structural strength of the product are improved.