High viscosity melt metering pump is a positive displacement pumping equipment, the same as the constant volume to transport the melt, so that the export pressure is not the same as the entrance pressure changes, is an excellent booster, voltage regulator. Is now widely used in tubing, profiles, sheet, film, cable, composite co extrusion and large extrusion granulation heat plastic extrusion production line, and the engineering application of the depth and breadth of the expanded day by day. Application of metering pump assisted extrusion, not only can obtain the required pressure, reduce energy consumption, and can reduce the shear heat, reduce the torque demand and reduce the pressure fluctuation, so as to improve product dimensional stability, control the melt quality, reduce the waste of raw materials, increase production, extend the service life of the equipment. In this paper, the mechanism, main performance characteristics and application prospect of high viscosity melt metering pump are analyzed in detail. Based on the extraction of a large number of literature data, combined with engineering practice, the general method and principle of application design of high viscosity melt metering pump is put forward. At the same time, the feasible solutions are put forward to the main technical difficulties in the application research. At the same time, the successful completion of the high viscosity of the melt metering pump in the twin screw extruder engineering application design, the full set of drawings to meet the construction requirements.