Abstract: The writing of Confucian classics in the Eight-legged Essay of the imperial examination in the Qing Dynasty can be comprehensively analyzed from the following three aspects: the origin of its Confucian classics attribute, the triple orientation of Confucian classics and the ecology of Confucian classics in Qing Dynasty. The Eight-legged Essay was the manifestation of externalization of Confucian classics which was the fundamental attribute of the Eight-legged Essay. The Eight-legged Essay containing annotation, textual research and studies of Commentaries of Gongyang, not only made it appear the trend of denying themselves, but also nurtured the Confucian classics, both of which had the same origin and development. The discourse of Eight-part Essay is integrated into the context of Confucian classics, which diluted and dispelled the position of standing on behalf of sages and changes from pure literariness to Confucian classics creation. It changed the academic writing style of classics and annotation, which highlighted the self-innovation and self-affirmation in the evolution of Confucian classics and injected new era factors into traditional Confucian classics and promoted the communication of Confucian classics. The Eight-legged Essay is the new facet of the study of Confucian classics in the period of imperial examination and another origin of the boom of the Confucian classics in Qing Dynasty. It is the indispensable theme of non-mainstream classics data in the study of Qing Dynasty academic.