The present paper,reconstructing the history,in which Qing scholars since Qianlong and Jiaqing reigns accused Liu Xin,a leading scholars of Former Han(202 BC-8 AD),of academic forgery and all these accusations were finally epitomized in Kang Youwei's well-known work exposing forged Confucian classics,argues that this rethinking effort is conducive to reevaluating the theoretical value of Kang's work and clari-fying origin and changes of key topics in Qing scholars'debate on old-text and new-text Confucianism.