ABSTRACT The tendency of herbicides to be adsorbed by the soil and their affinity to be desorbed are some of the most substantial factors influencing contamination of soil and water. Therefore, a kinetic and adsorption experiments were conducted to evaluate the adsorption of herbicide Fluazifop-P-butyl (FPB) onto two soils clayey and sandy clay loam soils using a batch equilibrium method. The experimental results of kinetic showed that the adsorption process was reaching equilibrium in 60 min, the kinetics of adsorption was well fitted by the pseudo-second order equation (R²>0.99). The adsorption coefficients of FPB was positively related with the clay and organic carbon content. Where (K_oc) were 2142.3 and 1914.3, (Kc)21.14 and 10. 67 for clayey and sandy clay loam soils, respectively. Adsorption data was more fitted to linear partitionmodel and to linear Freundlich adsorptionmodel. Freundlich constants (K_f) of FPB for the clayey and sandy clay loam were found to be 11.028 and 0.083, respectively. Distribution coefficients (K_d) were 11.15 and 2.01, respectively. The adsorption data also represented by Langmuir Isotherm model (R² were 0.96 and 0.92), the maximum monolayer coverage (q_m) was determined to be 46.65 and 1.038 mgkg^-1and the separation factor (R_l) were 0.0008 and 0.0834for clayey and sandy clay loam soils, respectively, indicating a favorable sorption experiment. The adsorption isotherm suggested a relatively higher affinity of FPB to the adsorption sites at low equilibrium concentrations. It was found that FPB has lower values of soil organic carbon partition coefficient (Koc) in the sandy clay loam soil, referring to its weak adsorption and thus increased its mobility. Hence, herbicide should be applied judiciously to avoid contamination