There are two kinds of Qidan scripts, the Big Script and tie Small Script. The Big Script is the one in which the Epitaph of Xiao Xiaozhong (蕭教忠墓誌) was written and which was discovered in Gushan Jinxi county, Liaoning province. This paper gives a general survey of the study of this important Qidan script during the past sixty years. It begins with the discovery of the extant inscriptions and the Epitaph of Xiao Xiaozhong, and chronicle the publications of the research work on the subject. The contributions of leading scholars such as Yan Wanzhang, Goro Toyada, Liu Fengzhu, Jin Yongtian and Ruan Tingzhuo are given notice. It concludes with the author's observations on the future research on the Qidan Big Script.