Sorption behavior of cobalt has been studied on illitic soil samples from dilute nitrate solutions using a batch technique, u'Co was used as tracer. Distribution coefficients (kd) were determined for the soil-cobalt solution system as function of contact time, pH, adsorbent, adsorbate and complementary cation concentrations. The effect of organic complexing ligands was also investigated. Desorption experiments were carried out to understand the sorption mechanism. The sorption was found to be rapid initially with slow rise later on. It was observed to increase markedly between pH 7-8 with maximum at pH 10. Percent adsorption increased with adsorbent concentration, while kd values first increased and then started decreasing. There was little effect observed with adsorbate concentrations in the concentration range studied. The data fit the Freundlich and Langmuir adsorption equations. Complementary cations, especially Ca and Mg, reduced the adsorption of cobalt. A 10 3 mol dm ~ concentration of synthetic organic chelating agents strongly inhibited the sorption of cobalt, while the natural organic ligands had little effect. The desorption experiments showed that sorption was irreversible. The soil under investigation has got the capability of fixation of cobalt and would be useful for the disposal of radioactive waste solutions.