A total of 8 typical soil profiles were selected as study objects, which are located in the Aba Tibetan and Qiang Autonomous Prefecture in Sichuan to explore genetic characteristics and taxonomy of soils in Zagunao Valley in the upper reaches of the Minjiang River. Through field survey of soil forming factors, the observation of soil morphological characteristics, and lab determination of soil physiochemical properties, soil types were determined according to Chinese Soil Taxonomy (CST) and Chinese Soil Genetic Classification (CSGC). Results showed that all the 8 soil profiles are of mesic temperature regime and ustic moisture regime. Soil hue is 7.5YR and 10YR, the values and chromas of some topsoils are lower than 3.5, meeting the color requirements of Mollic Epipedon. Silt fraction is the highest and clay fraction is the lowest, with the texture of loam or silty loam. Soil structures are mainly of sub-angular block, and the topsoils of some profiles are of aggregate structure. Moderate humic substances, clay film and CaCO₃pseudomycelium are found in some layers, indicating the existence of Argic and Calcic horizons. All soils have Calcaric property, mainly with alkaline to strongly alkaline reactions, and the content of calcium carbonate equivalents is ranged from 66 to 133 g/kg. The content of soil organic carbon is ranged from 1.64 to 61.45 g/kg, showing a gradual decrease with the increase of soil depth in some profiles and indicating the existence of Isohumic property. Free iron oxide content is reached from 10.78 to 19.57 g/kg and is over 14 g/kg in some layers, indicating the existence of Ferric property. Olsen-P content is reached from 1.2 to 43.1 mg/kg and meets the requirements of Fimic epipedon and Agric horizon in some layers. In CST, the studied soils are belonged to 4 orders of Anthrosols, Cambosols, Argosols and Isohumisols, 4 Suborders, 7 Groups and 8 Subgroups; while in CSGC, they are belonged to Dry-brown soil subgroup of Cinnamon soil group of Semi-leached soil order (corresponding to Calcaric Fimi-Orthic Anthrosols, Typic Hapli-Ustic Cambosols and Typic Molli-Orthic Cambosols in CST) and Calcareous brown soil subgroups of the same group and order (corresponding to Typic Pachi-Ustic Isohumosols, Typic Hapli-Ustic Argosols, Calcic Pachi-Ustic Isohumosols, Typic Calci-Ustic Argosols and Typic Ferri-Ustic Argosols in CST). Thus, comparatively, CST has stronger ability to distinguish soil types compared with CSGC.