Abstract: On September 12, 1850 (Aug. 7,30th year of Dao Guang, Qing Dynasty) a strong earthquake occurred in the Xichang-Ningnan region of Sichuan province. The provincial governor Xu Ze-chun submitted three memorials to the imperial government of Qing Dynasty successively.In this paper, a textual criticism of the earthquake hazard described in Xu's memorial to the throne is made on the basis of other historical documents and archaeological materials. As a result, the exaggerated and incorrect parts of the description are eliminated and the original state of the earthquake disaster is restored.