The invention relates to the technical field of injection molding devices, in particular to an injection molding device for plastic cup production, the injection molding device comprises a mixing bin, an auxiliary material
pipe, a transfer bin, a base material
pipe and a sliding
pipe, the sliding pipe is sleeved with a conical guide plate, the guide plate seals the transfer bin and the mixing bin, and the sliding pipe is provided with a vent hole; the bottom of the side wall of the sliding pipe is sleeved with the sleeve, a first
cutting hole is formed in the side wall of the sleeve, and a second
cutting hole is formed in the side wall of the sliding pipe; and cleaning the bin. According to the invention, material waste and material stockpiling requirements can be reduced, the condition of
caking after long-time material stockpiling is improved, the
mixing effect is better, the adding proportion of base materials and auxiliary materials can be adjusted in time according to products, the injection molding effect is improved, a small amount of materials are continuously mixed, the difficulty of cleaning the materials in the mixing bin is reduced, and the production efficiency is improved. The mixing bin can be quickly cleaned, the cleaning efficiency is improved, material residues in the mixing bin are reduced, and the product quality can be improved.