This paper deals with the modeling and optimization of the technological parameters of the injection molding process for the production of manholes from thermoplastic materials, specifically from polypropylene. The main goal is to determine the optimal process conditions to ensure high quality of the final product and minimize defects during molding. Before starting production, tests of the physical and mechanical properties of the plastic mass are carried out to verify its compliance with the technological requirements of the process. One of the key indicators of material analysis is the melt flow index (MFI), which in this case results in a value of 0.7 g/10 min, when tested under standard conditions of 190 °C under a load of 5 kg. This MFI value indicates an appropriate flow rate for the intended application, enabling complete filling of complex manhole shapes during injection.