The competition adsorption isotherms and kinetics of antimony (Sb) and phosphorus (P) on bentonite and kaolinite were investigated by bath methods; the effects of pH on their competition adsorption were also studied. The results showed that the adsorption of Sb and P was fitted to Langmuir or Freundlich equation (R²=0.9450 – 0.998 3, P<0.000 1), and strong competition adsorption occurred between them, where P decreased greatly Sb maximum adsorption capacity (Q_max) from 0.86 and 10.21 mmol/kg (first Sb after P addition) to 0.64 and 2.61 mmol/kg (first P after Sb addition), respectively; while Sb markedly reduced P affinity constant (K) from 1.47 and 7.47 L/mmol (first P after Sb addition) to 0.68 and 2.34 L/mmol (first Sb after P addition), respectively. The competition adsorption of Sb and P depended strongly on solution pH where the adsorption generally decreased significantly with the increase of pH. The adsorption by bentonite was more dependent on pH than one by kaolinite, resulted in more electrostatic adsorption on the former and more specific adsorption on the latter, respectively. The competition adsorption of Sb and P could fit well pseudo second-order kinetic equation (R²>0.994, P<0.000 1), where P adsorption on kaolinite was stronger and rapider (q_e=0.66 mmol/kg,k₂=0.591 kg/(mmol·min)) than that on bentonite (q_e=0.36 mmol/kg, k₂=0.0646 kg/(mmol·min)); Sb adsorption on the former was stronger and slower (q_e=0.39 mmol/kg, k₂=0.0524 kg/(mmol·min)) than that on the latter (q_e=0.19 mmol/kg, k₂=0.0769 kg/(mmol·min)). So, there was more Sb inhibition for P adsorption on bentonite (mainly a competition between electrostatic adsorption), and more P inhibition for Sb adsorption on kaolinite (mainly a competition between ligand adsorption).