The effects of Rhizobium fredii C6 on the adsorption of Cu on the colloids of red soil (RS) and yellow brown soil (YBS), goethite and noncrystalline Fe oxide (NFe) were studied. The results showed that the adsorption isotherm of Cu on soil colloids and Fe oxides in the presence of Rhizobium fitted Langmuir equation well(r>0.99) . There were greater amount of Cu adsorbed in the colloid systems of RS, YBS and goethite with the presence of Rhizobium than those in the corresponding systems without Rhizobium. The greatest increase of Cu adsorption was found in goethite (with smaller surface area) system. The system of Rhizobium and N-Fe adsorbed less Cu than pure N-Fe ( with larger surface area) system. The sequences of the amount of Cu adsorbed on examined soil colloids and oxides with and without the presence of Rhizobium were very different. With the increase of the number of Rhizobium in each system, the amount of Cu adsorbed on RS, YBS and goethite increased whereas decreased on N-Fe.