According to relevant standards,there are four main testing methods for diffusive hydrogen:glycerol method,mercury method, gas chromatography method and thermal displacement method. Among them,glycerol method has the characteristics of the most common application,the longest use time,the lowest test cost and the best safety,so it has been applied in the standard for a long time. However,the accuracy of glycerol method is low,especially in the case of ultra-low hydrogen,it is difficult to meet the requirements. The latest national standards are no longer recommended. Based on the discharging method of Tianjin University,a new diffusive hydrogen testing technology by glycerol method was realized through structural optimization and improvement. The results show that the precision of alkaline electrode E5015（Tianjin Bridge） used in electrode arc welding is 24%～28% higher than that of KQ-3 equipment,28% higher than that of CO,2, gas shielded welding and 28.7% higher than that of argon arc welding.