The adsorption of atrazine onto montmorillonite, attapulgite, bamboo-charcoal and charcoal were studied by using adsorption equilibrium experiments, the effects of pH and ionic strength were investigated and the Zeta potential of these adsorbents were analysed. It showed that the adsorption of atrazine onto these adsorbents were well fitted by the Freundlich isotherm and bamboo-charcoal and charcoal had much higher adsorption capacity to atrazine than montmorillonite and attapulgite. The adsorption quantity of atrazine onto adsorbents increased with the increase of ionic strength of bulk solution, that was, it increased from 538.30 to 611.26 mg/kg and from 609.68 to 731.63 mg/kg when the ionic strength was increased from 10-3 to 10-2 mol/L NaNO3 for montmorillonite and attapulgite, respectively. However, the adsorption quantity dramatically increased from 1 439.89 to 1 714.29 mg/kg when the ionic strength was increased from 10-3 to 10-1 mol/L NaNO3 for bamboo-charcoal. As the pH of bulk solution ranging from 3 to 8, the Zeta potentials of montmorillonite, attapulgite, bamboo-charcoal and charcoal suspensions possessed a negative value, indicating the pHiep (isoelectric point) of the above adsorbents lower than 3. Meanwhile, the Zeta potentials became more negative with the increases of pH and decreases of ionic strengths of bulk solution. The results would be helpful to understand the adsorption mechanisms of organic pollutions onto adsorbents.