Traditional enthalpy probe system use the Mass Flux Controller (MFC) to measure the flux rate of sample gas. However, this method much depend on the composition of plasma working gas under the condition of steady state of sample gas inside the probe, so it takes much more time to measure the enthalpy of a point. In order to overcome the disadvantage of traditional probe, the rapid enthalpy probe system we devised measure the molar weight of sample gas by using a known volume gas container instead of MFC, making it possible to measure the enthalpy of one point in several seconds. The accuracy of result acquired by our rapid enthalpy probe system is verified through our four different experiments.