A long-term fixed position experiment was carried out from 1987 to 1992 to study the efficiency of chloride-bearing fertilizer applied in farmland. The results show(1)in south Jiangsu where the evaporation and rainfall are close, to apply ammonium chloride was better than to apply urea in increasing crop yields, utilization rate of nitrogen, and the crude protein and amino acid contents of rice, wheat and rape; (2) increaseing times of applying ammonium chloride could nota- bly raise the utilization rate of nitrogen and improve the quality of crop seeds. (3) the accumulation of Cl^- in the soil inseased with the amount of ammonium chloride applied, but the accumulation and leaching of Cl^- in the soil went to equlibrium as the test continued and no accumulation of Cl^- in the plough and one-meter soil layer was discovered;and (4) the continuous application of chloride-bearing fertilizer could quicken soil acidfication.