Abstract: A method with ultra-performance liquid chromatography/tandem mass spectrometry(UPLC-MS/MS) for determining phthalanilic acid residue in soil was developed. The leaching behavior of phthalanilic acid in three types of typical soil(black soil, rice soil and red soil) was studied by soil thin layer chromatography. The results showed that the method fortified recoveries were between 77.3% and 99.4% with relative standard deviations(RSD) of 1.3%-11.4%.The limits of detection(LOD) could reach 1.0 μg/kg for the three types of soil. The relative flows(Rf) of phthalanilic acid in black soil from Jilin province, rice soil from Jiangsu province and red soil from Hunan province were 0.83, 0.61 and 0.62, respectively. It's found that the migrations of phthalanilic acid in black soil was in mobile grade,while moderate in rice soil and red soil.