A new method was established for the separation and enrichment of niclosamide in environmental water by cloud point extraction coupled with high performance liquid chromatography（HPLC）.With Triton X-114 as solvent,some factors affecting the cloud point extraction,such as surfactant concentration,pH value of sample solution,equilibration time and equilibration temperature on extraction efficiencies were studied and optimized.In the conditions of adding 3% Triton X-114 at pH 3.5,an equilibrium temperature of 45 ℃,an equilibrium time of 30 min and sodium chloride amount of 200 mg,the average recoveries were in the range of 95.6%-97.5%,and the limit of detection was 0.021 2 mg/L.With the advantages of high efficiency，environment friendliness and low cost，the method is suitalbe for the determination of drug residue in water samples of environment.