Cr(III) ions were biosorbed by Spirulina maxima algae. The pseudo-second order kinetic model was used for the description of biosorption kinetic data. The effect of pH (3-5), initial concn. of Cr(III) ions (100-300 mg/L) and biomass concn. (0.1-5 g/L) on the biosorption capacity was examd. The highest capacity 165 mg/g was achieved at the initial Cr(III) concn. 300 mg/L and biomass concn. 0.1 g/L. Under optimum conditions for biosorption selected (pH 5, temp. 20 degrees C, biomass concn. 1 g/L, initial Cr(III) concn. 200 mg/L) the biosorption capacity was 33.4 mg/g after 60 min.