it is a widely applied scintillant probing device to probe nuclear radiation, which has higher energy transfer efficient and better energy resolving power. It can be applied to X-ray and γ-ray probing and made into monocrystal or polycrystal with various dimensions and shapes.Our various specifications of ST111G NaI(TL)scintillant has good output consistency and the high temperature NaI crystal used for petroleum logging has three kinds of heat resistant performance: 150.C, 175.C and 200.C. The best resolving power of NaI(TL) is 6.2% when detecting with 137Cs and the probing effficiency is≥10%.