To obtain the temperature field of the radio frequency induction plasma torch in preparation of superfine powder, the governing equations for the coupled electric field, temperature field and flow field were set up based on heat transfer, electromagnetic theory, and incompressible Navier-Stocks equations. A numerical simulation of the electrothermal effect and fluid-thermal interaction in powder preparation were simulated using the finite element method, to obtain the velocity distribution and temperature distribution of the plasma torch in the flow process. The results show that a vortex exists in the plasma heating region, and the highest temperature point is not on the axial line of the region. The higher the power input, the smaller the distance between the highest temperature region and the coil for skin effect. Under the same gas flux condition, the distance between the highest temperature point and the coil is 0.062 m when the power input is 2 kW, and 0.039 m when the power input is 5 kW.