Studies on the possibilities of activating heavy metal ions by platinum ions in the soil have been undertaken. The present work gives results of research on the copper ions activated in loessial soil by the treatment with solutions containing platinum ions. Samples of podzolic soil developed from loess were collected from the horizon Ap (0-20 cm). The samples were treated with re-distilled water or with the same quantity of PtCl₄ water solutions containing 2, 4, 20 mg of platinum ions. Soil reaction (pH) was measured after 1, 2, 3, 4, 5 and 6 months of incubation at 5 and 20°C temperature. Copper ion content was determined in the filtrates using the technique of atomic absorption spectrometry. The amount of copper ions activated in the soil material depended on the soil reaction, temperature, quantity of platinum ions introduced and the time duration of the experiment.