The results of a 10-year liming field experiment and pot experiment indicated that(1)the reduction in the soil acidity and the increase in the contents of exchangeable Ca and Mg after application of powdered limestone resulted in the yield increase of green grain; (2) the reduction in soil acidity of the subsoil increased as the time of application of powdered limestone prolonged and lime rate increased, the effects of reducing soil acidity and increasing the yields of the crops could last at least 10 years; (3) the treatment with 7.5 t/ha powdered limestone significantly increased the contents of organic matter, total N, and available P; (4) the contents of available Zn and Cu of the soil increased as the pH increased and were significantly related to organic matter content of the soil, those correlation coeffioients were 0.965^** (n=5) and 0.887^** (n=5), respectively; (5) the contents of organic matter available Zn, and available Cu decreased with the increase of soil depth and (6) for red soil deficient in P, application of lime in combination with phosphorus fertilizer had an even better effect on the yield increase of soybeams.