Soil color is an important index of soil classification, climate reconstruction and environmental remote sensing. Iron oxides and humus are the two major chromogenic components of soil, which dominate the spectral response characteristics of soil. 【Objective】This paper is based on the unclear cross-coloration effect of iron oxides and humus in soils and sediments.【Method】 We selected kaolinite as substrate, hematite (Hm) and goethite (Gt) as the representatives of iron oxides, humic acid (Ha) and fulvic acid (Fa) as the representatives of humus. The spectral characteristics, color changes and cross-interference characteristics of iron oxides and humus with different contents were discussed by high-resolution Diffuse Reflectance Spectrum (DRS). 【Result】It is found that in terms of the chromogenic effect of a single component, Hm is stronger than Gt, and Ha is stronger than Fa. The addition of humus has an obvious effect on the coloration of iron oxides, which usually reduces the Mean Reflectance, Value (V) and Chroma (C), and makes the Hue (H) yellowish. The anti-jamming ability of Hm is greater than that of Gt. The a* of Lab color system and the redness of DRS are sensitive to the change of Hm content. The b* of Lab color system and the yellowness of DRS are sensitive to the change of Gt content. They can be used as indices for the quantitative determination of soil iron oxides. However, the addition of Ha can lead to the underestimation of Hm and Gt, and the addition of Fa has less effect on the estimation depending on the contents of Hm and Gt. 【Conclusion】Based on this, the estimation formulas of Hm and Gt mixed with different contents of humic acids are given. It not only helps understand the color change of natural soils but also lays a foundation for iron oxide determination at a large scale based on remote sensing.