Author has observed the relation between the parent rocks and the soils produced from the parent rocks in Kyung-gi and Kang-won Provinces, Korea and obtained the results as follows. The granite region has sandy or lcamy surface soils and sometimes clayey loam surface soils. The granite gneiss region has surface soils of sandy loam for the most part. The basalt region has surface soils of clay for the most part. The difference of the soil class largely accounts for the different rate of weathering of parent material in Korea.