【Objective】In order to comprehensively understand how the soils in the Helan and Liupan Mountains of Ningxia Province were developed and should be classified in soil taxonomy, a total of 10 soil profiles were selected out of the typical ones dug and prepared during the Soil Series Survey of Ningxia Province, 5 (Profile 3, 11, 13, 14 and 108) in the Helan Mountain and 5 (Profile 73, 82, 119, 120 and 121) in the Liupan Mountain area, for the study. 【Method】Firstly, locations of the 10 soil profiles were defined with the aid of ArcGIS and GPS; the profiles re-prepared for examination with soil-forming environment and profile morphology described and documented; and then soil samples collected from each soil layer of the profiles for analysis of physicochemical properties. 【Result】Based on the morphological characteristics and soil physicochemical properties of the 10 profiles, attempts were made to elucidate soil development features and determine niches in soil taxonomy. Results show that in the Chinese Soil Taxonomy, the 10 soil profiles could tentatively be sorted into the four soil orders, i.e. Primosols, Cambosols, Argosols and Isohumosols, five soil suborders, i.e. Orthic Primosols, Ustic Cambosols, Udic Cambosols, Boric Argosols and Udic Isohumosols, and six soil subgroups, i.e. Calcaric Aridi-Orthic Primosols, Typic Hapli-Ustic Cambosols, Typic Molli-Ustic Cambosols, Mollic Bori-Udic Cambosols, Typic Hapli-Boric Argosols, and Mottlic Hapli-Udic Isohumosols. Further on, they could tentatively be sorted into 10 soil families, i.e. Coarse bone sandysilica mixture mesic-Calcaric Aridi-Orthic Primosols, Coarse bone sandyfeldspar typical mesic-Calcaric Aridi-Orthic Primosols, Sandyfeldspar mixturecalcareous frigid-Mollic Bori-Udic Cambosols, Sandysilica mixture calcareous frigid-Mottlic Hapli-Udic Isohumosols, which are completely separated ones, and still further into 10 soil series, including Putaoquan series, Yidui series, Gunzhongkou series, Liupanshan park series, Lvyuanyao series, etc. 【Conclusion】Altitude is the major factor affecting development characteristics of the soils in the mountains of Ningxia. With rising altitude the soils show apparent humus accumulation processes, intensifying leaching processes through the solums, weakening lime reaction till nil, and improving soil moisture regime. At the bottoms of the solums of the mountain soils high in altitude, weak redox reaction occurs, forming iron and/or iron-manganese colloids and reducing soil pH, thus causing certain changes in soil acidity and alkalinity. Affected by the soil forming environment and factors, soil development rules are reflected in the diagnostic horizons as a certain vertical variation rule along the altitude. The diagnostic surface horizons have their mollic epipedons turned into ochric epipedons, their soil moisture regimes from aridic/ustic into udic, and their soil temperature regimes from mesic into frigid.