The invention relates to a plastic enclosed impeller manufacturing technique of a plastic lining pump. The plastic enclosed impeller manufacturing technique is characterized by comprising the following processing steps: adding 720 grams of tetrafluoroethylene-hexafluoropropylene copolymer granules into the mold of a front shroud, heating the tetrafluoroethylene-hexafluoropropylene copolymer granules to 320 DEG C +/- 2DEG C in a heating box, carrying out heat preservation for 3 hours, then pressurizing 10 MPa in a pressing machine, maintaining pressure for 2 hours, carrying out natural cooling in air, and demoulding to take out a front shroud; adding 512 grams of tetrafluoroethylene-hexafluoropropylene copolymer granules into the mold of a back shroud, heating the tetrafluoroethylene-hexafluoropropylene copolymer granules to 320 DEG C +/- 2DEG C in the heating box, carrying out heat preservation for 2 hours, then pressurizing 10 MPa in the pressing machine, maintaining pressure for 1.5 hours, carrying out natural cooling in air, and demoulding to take out a back shroud; and using teflon bar materials to process screws to connect the front shroud and the back shroud. The manufacturing technique guarantees the separated pressing of the front shroud and the back shroud through a pressing technique, a blade can be made into a double curvature shape, and therefore the hydraulic performance of an impeller is improved, and a manufacturing technology is simple, production cost is low, and the plastic enclosed impeller manufacturing technique can meet the usability of the plastic enclosed impeller completely.