唐宋時期多依五姓墓葬法來選擇葬地，此中尤為重要的當屬六甲八卦冢法，直至元代仍有以此法作為擇葬理據者。然而關於六甲八卦冢的概念及運算法則，一直以來並未解釋清楚。將唐宋時期風水書籍的資料記載與墓葬的實際數據相結合，對六甲八卦冢葬法的具體計算方法進行核驗與分析，可以明晰彼時的擇穴依據與推算法則。除了釐清六甲冢與八卦冢二者之間的關係與判斷方法，還能辨明在營建理想墓穴時所採用的「禽交」、「六尺」兩種定穴標準。此外，有關墓穴定位的七分法與十三分法的問題，也因此可以得到解決。

During the Tang and Song dynasties, grave placement was based on a set of techniques known as the “five surname method” (wuxing fa 五姓法), of which the most important was the “liujia bagua mound method” (liujia bagua zhongzang fa 六甲八卦冢葬法). Despite its popularity and its continued use until the Yuan dynasty, the concept and algorithm informing the liujia bagua method has yet to be adequately explained. Combining the procedures recorded in fengshui texts from the Tang and Song dynasties with actual data from excavated tombs, this article clarifies the criteria used for tomb selection by analyzing and verifying the calculation procedures of the liujia bagua method. In addition to explicating the methodology involved in selecting liujia and bagua tombs, the two location standards of qinjiao 禽交 and liuchi 六尺 are also explored.