The biosorption of cadmium and lead by Penicillium sp. isolated from an uncontaminated soil was studied at different initial metal ions concentrations. The maximum removal yields were obtained at 5 mg/L initial metal concentration. The highest removal yields were 35.67% and 81.99% for cadmium and lead, respectively, in the single system. In the binary system, the removal yield increased to 90.99% and 97.48% for both metal ions at the same initial concentration. This study has also confirmed that Penicillium sp. was able to grow in the presence of both metal ions at different concentrations. In addition, this study showed that Penicillium sp. was more tolerant to cadmium than lead. Fungi have also shown a tolerance to high oncentrations of toxic heavy metals. This study can provide useful information on the bioremoval of heavy metals such as Cd(II) and Pb(II) from wastewaters.