The aim of this study was to determine the effects of copper contamination (0, 50, 100, 150, and 200 mg Cu/kg of soil) and neutralising substances on the content of total organic carbon, total nitrogen, available forms of phosphorus, potassium, and magnesium, and C:N ratio in soil. The experiment was conducted in four series: without neutralising substances and with compost 3% of soil weight, bentonite 2% of soil weight, and zeolite 2% of soil weight. Contamination of soil with copper and the application of the neutralising substances had a significant effect on soil properties. Contamination with copper in the series without substances increased the content of total nitrogen and available phosphorus, potassium, and especially magnesium. Copper also widened the C:N ratio in soil. All of the amendments applied to the soil had the strongest effect on the content of total nitrogen and the C:N ratio in soil. They reduced the content of total nitrogen and widened the C:N ratio. Amendments also increased the content of available magnesium in soil. The effect of the substances applied to soil on the content of the other elements was significantly weaker, as it changed by up to 12%.