【Objective】This paper is to characterize dimethyl phthalate (DMP) migration and release between overlying water, pore water and soil in the water level fluctuating zone of the Three-Gorges Reservoir during the wetting-drying alternation period.【Method】For the study a flooding experimental device was designed to carry out cyclical wet-dry alternation test using the "flooding-drying" model. 【Result】DMP content was found decreasing significantly in the soil during the first days (0~2 d) of the two flooding periods, but increasing from the third day on, and fluctuating slightly in the pore water and overlying water；it displayed a rising trend to a varying extent in the soil on the first days (0~1 d) of the two drying periods, and a declining one varying in degree on the following two days (2~4 d), and then leveled off during the late period (8~20 d). Soils with initial DMP content varying in the range of 10 ~ 100 mg•kg^-1, when flooded, showed a similar trend in DMP migration and release between the three phases. However, DMP content in the overlying water showed a different trend from the other three groups, and the DMP distribution fluctuated greatly in the three phases，when soil initial DMP content was 200 mg•kg^-1.【Conclusion】The quasi-second-order kinetic equation can be used to well describe migration of DMP in pore water and overlying water into the soil. Correlation analysis shows a significant positive correlation (P<0.05) exists between pore water and overlying water in DMP concentration, but a mildly negative one between soil and pore water.