Abstract: The physical properties of insoluble liquid pollutants floating on water surface are important factors affecting the release intensity to subjacent waterbody. According to the physical properties and the range of related parameters of organic pollutants, 8 representative insoluble floating liquid pollutants were selected, and 32 mixed samples were prepared with them in different proportions. The density, kinematic viscosity, and surface tension of 39 typical samples are ranged from 0.621 to 0.995 g/cm³, 1.81×10⁻⁶ to 1.00×10⁵ mm²/s and 0.024 to 36.200 mN/m, respectively. The effects of pollutant density, kinematic viscosity, and surface tension on release intensity of the 34 samples from the 39 typical samples are studied through laboratory flowing water physical experiments, and the key physical factors affecting the release intensity were identified by partial correlation analysis. The results showed that the decisive factors affecting the release intensity are density and kinematic viscosity, while the surface tension has no significant effect on release intensity. The multivariate nonlinear regression model between release intensity, density and kinematic viscosity was established with regression analysis (R²=0.987). The model was verified through experiments with remaining 5 independent experimental data from the 39 typical samples, and the average relative error is 14.9%.