Abstract:Lou soil, which is profoundly influenced by the agricultural activities, is an important agricultural soil in the Guanzhong area of Shaanxi Province, but disputes still exist nowadays on its genetic process and classification in recent years. In this paper, we reviewed the soil formation process and genetic characteristics, summarized the alteration of Lou soil in the genetic classification system in the past years, identified the diagnostic horizons, diagnostic characteristics and diagnostic evidences in Chinese Soil Taxonomy, predicted the spatial distribution of the senior taxon (soil order, suborder, group and subgroup) in the area and established the diagnostic indicators for the basic taxon (soil family and series) in Chinese Soil Taxonomy for Lou soil. Finally, three future research focuses were proposed for the Lou soil: 1) Further understand the influences of human agricultural activities on Lou soil formation process to quantitively understanding the formation process of cumulic epipedon; 2) Study the thickness of the cumulic epipedon to determine the scientific depth criteria of the cumulic epipedon in Chinese Soil Taxonomy; 3) Conduct soil survey to establish the representative soil series of Lou soil.