The role of biofilm covering on sediments in the adsorption of three endocrine-disrupting chemicals(EDCs), 17α-ethinyl estradiol(EE2), bisphenol A(BPA), and 4-nonylphenols(4-NP), was investigated. The results indicated that the organic carbon(OC)-normalized distribution coefficients(k_oc)of BPA, EE2, and 4-NP ranged from 10^{1. 78} to 10^{3. 02} L/kg. After the oxidation of sediments by H₂O₂, the k_oc of EE2 was higher(10^{2. 32} L/kg)than before the oxidation(10^{2. 19} L/kg). A two-stage adsorption(fast adsorption and slow adsorption)kinetic model was established(r²>0. 95). The simulation results showed that the fast adsorption section played the main role in the adsorption process, while the slow adsorption section determined the extent of the reaction. The biofilm on the surface of sediments may act as a barrier in mass transfer from water to sediment and seldom improve the adsorption capacity of sediments.