As an initial analysis, numerical simulation has more advantages in saving time and costs compared with experiments. Variations in flow conditions and geometry can be adjusted easily to get results. CFD methods with k-ϵ model, RNG k-ϵ model and Reynolds Stress Model (RSM) widely used in research on objects and different conditions, to be produced on the appropriate model to use and the development of value constants. Modeling studies appropriately in the turbulent flow simulation in the crossflow turbine nozzle is done to get a more accurate result. The study was conducted by comparing the results of the simulation k-ϵ model, RNG k-ϵ model and Reynolds Stress Model (RSM), which is validated by the test results. The air gas has a static pressure of 1,55 bar, a temperature of 971 K, a density of 0,39 kg/m3, a viscosity of 4×10-5 m2/s and a mass flow rate of 0,32 kg/s. By comparing the simulation results k-ϵ model, RNG k-ϵ model and Reynolds Stress Model (RSM), which is validated by the test results the third model of turbulent give good results to predict the distribution of velocity and pressure of the fluid flow in the crossflow turbine nozzle. As for predicting the turbulent kinetic energy, turbulent dissipation rate, and turbulent effective viscosity, RSM turbulence models recommend to be used for complex physical geometry.