Abstract: This paper mainly introduced some researches about calibration of scintillatorssensitivity using standard radio -active sources 241Am, 133Ba and 152Eu in Beijing Institute of Atomic Physics. As a scintillator could be used for single photon counting, are developed a new method to calibrate a scintillators sensitivity by measuring detectors' charge spectrum with radioactive sources' incidence. The experiment also calibrated QDC(quantity-to-digital convertor), and got the results of sensitivity for Filter-Fluorescer spectrometer in ICF experiments. The data's uncertainty (10%) was lower than that with traditional methods (15%), and calibration energy range increased up to more than 100 keV. Finally, we compared experimental data with Geant4 simulating results, and they were in good accordance.