The Wafangdian Diamond Mine in southern Liaoning is the largest diamond mining area in China, where four diamond metallogenic belts and 120 rock bodies have been discovered. Among them are 24 kimberlite pipes, 89 veins, and 7 suspicious rock bodies with a total of 12. 21 million carats of reserves accounting for 52% of the national diamond reserves. This study mainly carried out a comprehensive analysis of the rock geochemical characteristics of the diamond mother rock—kimberlite and determined contents of MgO, NiO, Cr 2O 3 in kimberlite and the alkaline nature of TiO 2, Al 2O 3, Na 2O, K 2O, CaO, P 2O 5, etc. The trace element contents of Ni, Cr and Co are positively correlated with the diamond content, while the contents of basic elements such as Ti, Zr and Ba show a negative correlation. Diamond minerals can be located by summarizing various geological temperature and pressure gauges such as garnet and monoclinic inclusions, olivine- garnet mineral pairs, garnet trace elements, spinel- olivine in diamonds in the Wafangdian mining area. The source depth is 150~210 km, the pressure is 5~7GPa, and the temperature is 1083~1261℃. Under the above temperature and pressure conditions, combined with the chemical composition of magma, it is estimated that kimberlite has low oxygen fugacity (fO 2=2. 913×1. 01325×10-6Pa) features. This paper summarizes the field exploration work, geological characteristics, ore- controlling structure, ore body spatial distribution and other factors of the deposit. It is believed that the NEE and NE faults control the distribution of the kimberley rock mass and the ore body morphology. Veined kimberley rocks are generally distributed in the direction NEE 70°~80° and are strictly controlled by dense joints or fissures oriented NEE to near EW. It is proposed that the diamond mother rock—kimberlite was derived from the upper mantle magma, under confined conditions, controlled by both structure and lithology, and formed by multi- stage alternating explosions and intrusions, and with high oxygen. The rheological asthenosphere with high fugacity, high density and enriched chemical composition is the ideal genetic model of diamond formation by infiltration of the lithosphere by melt. This study aims to provide guidelines for the future prospecting work.