The quality of spray-formed parts is the most important research field in plasma spraying, which has been developed in rapid forming the materials of difficult processing such as ceramics, high melting point alloy and composite materials in recent years. It is insufficient to research the forming quality affected by the plasma-particle interaction based on the plasma characteristics. The temperature field distributions of plasmajet have been investigated under the different conditions by imaging and processing, and the experimental measurements of surface temperature for in-flight particle have been carried out by the principle of two-wavelength pyrometer. At the same time, the mathematical models of momentum and energy transfer have been established to analyze the motion laws and temperature distribution of in-flight particles during spraying. The results show that the temperature field distribution of plasma jet is obviously affected by the components of working gas, the forming quality is significantly influenced by the flight time and melting state till arriving at the spray mould, in which the mechanical behavior and the heating characteristic of plasma-particle interaction in spraying system should be properly matched with each other. The mathematical simulations of temperature are in a good agreement with experimental results.