The relevant provisions of bloodletting for expelling pathogens are collected from the works of the medical representative scholars in Jin-Yuan Dynasties and Ming-Qing Dynasties respectively to construct the databases of bloodletting for expelling pathogens of Jin-Yuan Dynasties and Ming-Qing Dynasties. Using frequency analysis, the bloodletting device, bloodletting location, bloodletting volume, the related pathogens and indications are compared between these two times so that the evidences could be provided for the inheritance and development of the academic thought of bloodletting for expelling pathogens. It is found that the three-edge needle is the most commonly used device for bloodletting in Jin-Yuan Dynasties and Ming-Qing Dynasties and yang meridians and local affected area are generally selected for bloodletting. The range of meridian and acupoint selection in Ming-Qing Dynasties are more extensive than those in Jin-Yuan Dynasties, while bloodletting volume is less than that in Jin-Yuan Dynasties. In Jin-Yuan Dynasties, bloodletting therapy is mainly for expelling exogenous pathogens i.e. heat, fire and wind, while, in Ming-Qing Dynasties, this therapy is specially for clearing heat and removing stasis. The disorders of internal medicine are often treated with such therapy in these two dynasties. But, compared with Jin-Yuan Dynasties, the indication of bloodletting therapy is expanded gradually in Ming-Qing Dynasties. It is shown that the academic thought of bloodletting for expelling pathogens in Jin-Yuan Dynasties is inherited and developed from Ming-Qing Dynasties.
整理金元和明清时期代表医家相关著作中有关刺络祛邪的条文，构建金元-明清时期刺络祛邪数据库，运用频次分析比较刺络工具、刺络部位、刺血量、所祛之邪、主治病证的异同，为刺络祛邪学术思想的传承与发展提供依据。发现金元及明清时期使用最多的刺络工具均为三棱针，刺络部位均以阳经和局部为主；明清时期在经脉和穴位选择上较金元时期更广泛，而刺血量少于金元时期；金元时期刺络祛邪主要针对热、火、风等外感之邪，明清时期则以热、瘀血居多；主治病证均为内科病，与金元时期比较，明清时期主治病证范围逐渐扩大。明清时期继承并发展了金元时期刺络祛邪学术思想。.
Keywords: Jin-Yuan Dynasties; Ming-Qing Dynasties; bloodletting device; bloodletting for expelling pathogens; bloodletting volume.