Abstract: The Maoming Basin belongs to a half grabenlike faulting basin of extension regime. The oil shales are found both in the Palaeogene Youganwo Formation and in the Neocene Shangcun Formation. The Youganwo Formation is the main mining horizon where the oil shale lies on the top of coal beds. The sedimentary environment of the oil shale belongs to a moderate deep lake system. The Jintang mine in the Maoming Basin is located in the richest center of the basin. A fault trending northwest controlled the buried depth, distribution and oreforming process of the oil shale. Affected by the sedimentary environment and their provenances, the oil yield of the Youganwo Formation is commonly within a range of 5％ and 9％, up to 13％; the oil yield of the Shangcun Formation changes in a range of 3.5％ and 6.5％, averaged at 4.5％.

Key words: oil shale, sedimentary facies, depositional evolvement, distributing rules