The physical model of the streamline jet nozzle was established according to the mathematic expression. According to the design parameters of the actual project, streamline nozzles with different height were numerically simulated by using the FLUENT software respectively. The influence of different height on the nozzle jet performance was researched through the analysis of the physics distribution rule of velocity, pressure and turbulent kinetic energy of the nozzle jet flow field. The results show that the streamline nozzle height must be chosen between 30d to 35d values as the best, which provides a reference for the height and other nozzle structural parameters design.