The labyrinth screw pumps are widespread in the chemical and oil industries. The scope of the possible use of the labyrinth-screw pumps working in aggressive mediums is much wider in comparison with the pumps with similar pressure and flow parameters. This is due to the type of operation and lack of the mechanical friction of the parts. Increasing the pump flow rate can be achieved by reducing hydraulic friction resistance or profiling the inlet and outlet of the fluid flow. The flow channel of the labyrinth screw pump has been improved and a new design of its movable operating elements has been developed based on the proposed concept of jet resistor diodes. The reduction of hydraulic resistance in the flow channel of the pump with the working fluid flow in the forward direction and increasing the resistance of the diode made it possible to obtain a more efficient design. The results of improvement are compared with experimental data. The simulation of the flow in the pump is performed by solving the RANS equations with the SST turbulence model. The flow predictions in the flow section are obtained. The flow rate characteristics of typical and developed pumps are calculated. The developed pump design allows for increasing its flow rate by almost 10%. At the same time as the flow rate of the pump increases its power output. The efficiency of the industry-developed labyrinth screw pump application is proven by comparing the flow rate characteristics of the pumps.