Abstract: Gamma rays of different energy were obtained in the range of fission energy by Compton scattering in intense 60Co gamma source and the standard isotopic gamma sources which are 0.67 MeV 137Cs and 1.25 MeV 60Co sources of point form. Sensitivity of LaCl3:Ce scintillator was measured in these gamma ray energy by a fast response scintillation detector with the home-made LaCl3:Ce scintillator. Results were normalized by the sensitivity to 0.67 MeV gamma ray. Sensitivity of LaCl3:Ce to 1.25 MeV gamma ray is about 1.28. For 40 mm×2 mm LaCl3:Ce scintillator, the biggest sensitivity is 1.18 and the smallest is 0.96 with gamma ray from 0.39 to 0.78 MeV. And for 40 mm×10 mm LaCl3:Ce scintillator, the biggest sensitivity is 1.06 and the smallest is 0.98. The experimental results can provide references for theoretical study of the LaCl3:Ce scintillator and data to obtain the compounded sensitivity of LaCl3:Ce scintillator in the range of fission energy.