Abstract: Batch experiments were conducted to investigate the effects of decomposed dairy manure on the adsorption of bisphenol A (BPA) onto loess soil. The influence factors, such as temperature, initial concentration, ionic strength, pH, were also investigated to analyze and explore the changes of BPA adsorption onto loess soil affected by adding decomposed dairy manure. The results showed that the adsorption rate of BPA onto loess soil was fast initially and then slowed down before reaching the adsorption equilibrium. The adsorption kinetics curves of the loess soil with or without presence of decomposed dairy manure were all fitted well with the Pseudo-second-order model. The amount of BPA desorption from loess soil with or without the presence of decomposed dairy manure was much smaller than the adsorbed BPA, showing the existence of hysteresis in the sorption-desorption processes. The thermodynamic adsorption conformed to the Freundlich adsorption isothermal model, and was consistent with the L-type adsorption isotherm. The adsorption free energy of BPA was all less than zero, such as gibbs free energy (ΔG^θ), enthalpy (ΔH^θ), and entropy (ΔS^θ), which indicates that the adsorption was a spontaneous process and the degree of chaos was reduced. The adsorption capacity of BPA onto loess soil increased with the decrease of particle size. The adsorption of BPA onto loess soil with or without the presence of decomposed dairy manure decreased with increasing temperature. In addition, the cations competed with BPA for adsorption, and with the increase of ion strengths, the inhibitory effects of BPA onto loess soil with the presence of decomposed dairy manure were higher than that without decomposed dairy manure. When pH was between 3 and 7, the adsorption capacity of BPA increased with the increase of pH, and the adsorption capacity of BPA was small when pH was between 7 and 10, which means that the alkaline conditions had little effect on the adsorption of BPA onto loess soil. The results suggested that the adsorption behavior of BPA onto loess soil may be changed by decomposed manure.