Adsorption experiments were conducted with three soils to determine the characteristics of adsorption and the factors affecting adsorption of permethrin in soil. Permethrin was adsorbed in batch experiments within two hours. Adsorption isotherms followed the Freundlich equation (r 2 = 0.71 –0.98) and most of them were classified as S‐curves implying a catalytic adsorption. Comparison of the Freundlich k coefficients in relation to the properties of the soils suggests that the size of aggregates is the most important factor affecting adsorption of permethrin, followed by the organic carbon and clay content. Cation exchange capacity and pH has no significant effect on adsorption of permethrin. The mean Koc value of permethrin (159,000) accounts for the reported low mobility of permethrin in soil. Cis‐permethrin was adsorbed to a greater extent than trans‐permethrin which may explain its reported lower mobility and lower rate of degradation.