The influence of pH on the dissolution of aluminum in acid soils and the distribution of aluminum ion species in soil solution were studied. The results indicated that the dissolved aluminum increased with the decrease in pH The effcet of pH on the dissolution of aluminum varied with the soil type. The extent of pH influence on the dissolution of aluminum in three acid soils was in the order red soil>lateritic red soil>latosol. It suggested that the sensitivity of aluminum dissolution to external acid was different among the three soils. The distribution of aluminum ion species in soil solution varied with pH The proportion of Al³⁺ to total monomeric inorganic aluminum increased with the decrease in pH but that of Al-F complexes increased with the increase in pH Within the range of studied pH the proportion of Al-0H species was not higher than 5 percent. Temperature affected the aluminum dissolution and the distribution of aluminumion species in soil solution. Both the dissolved aluminum and the proportion of Al³⁺ species increased with the drop in temperature, but the proportion of Al-F complexes varied with temperature in an opposite trend. A decrease in pH resulted in a decrease in the proportion of polymeric aluminum ion species in soil solution. Therefore its rtion was very small in acid to strongly acid soils (pH<4.5). The results obtained from the red soil and latosol indicated that the solubility of aluminum in soil solution was controlled by aluminum oxides in soils.