The adsorption of copper ions on humus was studied depending on the different initial concentrations of copper solutions (5.255 mmol dm-3, 10.081 mmol dm-3, 12.175 mmol dm-3, 23.255 mmol dm-3, 38.181 mmol dm-3). The experiment has been carried out at a constant temperature of 318 K, stirring speed of 200 rpm for duration of 96 h. Based on the results obtained, it can be concluded that the amount of copper ions adsorbed (qe) changes slightly with the increase of the initial concentration of copper ions in solution (c0), reaching its maximum value at an initial concentration of 38.181 mmol dm-3 with the value of qe = 0.529 mmol g-1 for the conditions under which the experiment was conducted. The copper adsorption efficiency reaches its maximum value for the lowest selected initial concentration of 5.255 mmol dm-3, with the value of 48.032 % and then decreases with the increase of the initial concentration of copper ions in solutions. Considering the quality of the agreement of the adsorption models with the data obtained experimentally, as well as the comparison of the calculated values of the maximum adsorption capacity of copper ions with those obtained experimentally and the statistical parameters for RMSE, χ2 as well it can be concluded that the best agreement with the experimental data is shown by Toth’s adsorption isotherm.