Soil aggregate is the basic structure unit of soils and the ability of various size fractions are different in the aspect of adsorbing and transferring heavy metals in the environment. In this study, bulk soil from red paddy field was partitioned into four aggregate-size fractions and their adsorption characteristics for Cu and Zn were studied. Our results showed that: Pseudo-second order model was more successful to fit the adsorption process in the kinetic experiments and the isothermal experiments data can be described well with the Freundlich model as a whole. Due to higher contents in organic matter, CEC and free iron oxide, the