The composition characteristics of clay minerals and iron-aluminum oxides at different horizons of soil profiles in the vertical zonal soils of the Jiugong Mountain in Hubei Province were studied to reveal the changes of clay minerals in mountain soils. The results indicated that the content of kaolinite was abundant in soil at lower altitude, whereas the majority was 14.0? minerals, illite and gibbsite at higher altitude. With the increase of altitude, there was a transition trend of clay minerals from 1:1 to 2:1 types. The changes of types and relative contents of clay minerals in soils were obvious at differe?nt horizons in soil profiles. With the increase of altitude, the contents of free iron-aluminum oxides decreased but those of amorphous and complex iron-aluminum oxides increased in clays, and the total amounts of iron-aluminum oxides in different forms were also increased.