An adsorption and desorption test was conducted of two variable charge soils (Ali-Haplic Acrisol from Jiangxi and Hyper-Rhodic Ferralsol from Kunmin of Yunnan) to explore distribution of desorption rates of pre-adsorbed Cu(II) from the soils in NaNO₃ solution relative to concentration of the solution and pH, at which Cu(II) was adsorbed during the pre-adsorption phase. For the test, the soil samples were first put into de-ionized water and 0.1 mol L^-1 NaNO₃, separately, for pre-adsorption of Cu(II) and then into de-ionized water and NaNO₃ solutions varying in concentration gradually from low to high, sequentially, for desorption of Cu(II). Results show that with rising pH, Cu(II) desorption rate varied sharply with NaNO₃ solution. In de-ionized water, Cu(II) desorption rate declined monotonously with the rise of pH in the Cu(II) pre-adsorption phase; while in NaNO₃ solutions, Cu(II) desorption rate followed a peak-shaped curve, but the total Cu(II) desorption rate also declined monotonously with the rise of pH in the Cu(II) pre-adsorption phase. The Cu(II) desorption rate was the highest in the solution of 0.1 mol L^-1NaNO₃. In short, desorption rates of the Cu(II) desorbable in de-ionized and in NaNO₃ solutions were distributed mainly in the high and low sections, respectively, of the range of pH studied. Desorption rate of the Cu(II) desorbable in NaNO₃ was closely related to content of ferric oxide in the soils and NaNO₃ concentration in Cu(II) pre-adsorption, so the higher the content of ferric oxide in the soil, or the higher the NaNO₃ concentration in pre-adsorption at pH > 4.0~4.5, the lower the proportion of Cu(II) desorbed by NaNO₃. The cause of such a phenomena is believed to be associated with the effect of ion-strength, specific weight of exchangeable Cu(II) relative to adsorption condition and the effect of desorption on pH of the system. Besides, comparison was also made between sequential desorption in solutions constant in NaNO₃ concentration and that in solutions varying in NaNO₃ concentration.