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重金属是土体污染中最重要的污染物质之一，土中的重金属污染往往是复合污染的形式。通过一系列室内试验，研究了锰铬重金属共存时在黄土上的吸附特性。在Mn(II)、Cr(III)重金属复合体系中，Mn(II)在黄土上的吸附明显受到抑制，吸附量减小14.6%～46.5%，而 Cr(III)在黄土上的吸附基本不受Mn(II)的影响。Mn(II)的吸附能较好地符合Langmuir模型，受Cr(III)的抑制而不能很好地符合Fredunlich、D-R模型，Cr(III)的吸附仍能较好地符合Fredunlich、D–R模型。在pH=5～7酸性条件下Cr(III)促进了Mn(II)在黄土上的吸附，Mn(II)对Cr(III)的吸附稍有抑制；在碱性条件下， Cr(III)基本不受影响能完全被去除，而Mn(II)的吸附受到很大的抑制作用。重金属本身的物理属性比如水解常数大小以及黄土中的矿物成分都对Mn(II)、Cr(III)在黄土上吸附特性发挥了重要作用。“,”Heavy metal is one of the most important pollutants in soil, and heavy metal-combined pollution is the most common form. Behavior of Mn(II) and Cr(III) adsorption in loess soil is studied through a series of experiments in laboratory. Adsorption of Mn(II) is found to be inhibited in Mn(II)-Cr(III)-combined system and the adsorption capacity decreases by 14.6%~46.5%, while adsorption of Cr(III) is basically not influenced. Mn(II) adsorption agrees well with that of the Langmuir model but not with that of the Freundlich and D-R models, while Cr(III) adsorption still agrees well with that of the Freundlich and D-R models. At pH around 5~7, removal of Mn(II) becomes more efficient, and that of Cr(III) becomes less efficient. Under alkaline condition, Cr(III) is almost completely removed, but Mn(II) removal is inhibited greatly. The physical property of heavy metal (i.e., hydrolysis constant) and minerals in loess soil both are found to play important roles in adsorption of Mn(II) and Cr(III).