Abstract: The Wafangdian area is one of the famous primary diamond mineral deposits in China, where diamonds from nearly one kilometer of ore bodies have been eroded to form valley placers, terrace placers, and conglomerate ancient placers. However, there has always been significant controversy and disagreement in the academic community regarding the source of metallogenic materials for conglomerate type diamond deposits, which seriously affects and restricts the geological exploration and even the direction of exploration of this type deposit. The Rentun conglomerate type ancient placer mine in Wafangdian is characterized by its near surface, loose cementation, easy mining and selection, high grade, and high economic value. Therefore, this paper takes this mine as an example and uses methods and means such as field geological survey, mineralogy, and geochemistry to conduct research on the distribution, lithology, and mineral composition characteristics of conglomerate, at the same time, based on the comparative analysis of conglomerate diamonds and their associated minerals with known rock pipes in Wafangdian, it is believed that the Rentun conglomerate type diamonds do not originate from known rock pipes, but rather from the undiscovered kimberllite rock that invaded the Cambrian strata nearby, and the grade of the rock pipes is considerable.