Abstract: The reference leak used for calibration of halogen leak detectors has always had a high degree of uncertainty. In order to reduce the uncertainty of halogen leak rate values, a method for reproducing leak rate based on gas reference material was proposed. The conversion relationship between gas concentration and leak rate under specific conditions was obtained through formula derivation and verified through experiments. The results showed that the consistency between the reproduced leak rate and the standard leak rate measured by halogen leak detector was excellent (the normalized deviations of the two experiments were 0.41 and 0.21). The components of uncertainty of the reproduced leak rate were analyzed, including gas reference material, inhale flow, temperature, pressure, molar mass and gas constant. After calculation and synthesis, the relative expanded uncertainty of the reproduction leakage rate based on gas reference material was obtained as 2.5% (k=2), which is significantly lower than that of common reference leak, also the method has good operability.