A new method of scanning thin-layer chromatography was established for the quantitative determination of the 4-chloro-3,5-dimethyl phenol by developing with 40% benzene in trichloromethane on GF254 silica gel plate. The results showed that the linear dynamic range of 4-chloro-3, 5-dimethyl phenol was 0.1858 g/L-7.4320 g/L in which the relative peak area obeyed the Lambert-Beer's law with a correlation coefficient of 0.9994 and recoveries of 98.31%-100.1%. The method is simple, rapid, sensitive and reproducible.