Arsenic (As) is one of the highly toxic elements, and many diseases have been linked to the consumption of arsenic containing water in many places of the world. The As (III) adsorption capacity by AA and the effects of organic phosphorus, S2−, pH and PO43− on the As (III) removal by AA was studied. The results showed that AA is a adsorbent for effective As (III), and the maximal adsorption capacity for As(III) is 3.6mg/g. At the pH of 5.5–8.5, AA exertes better As (III) removal efficency. Competitive anions trials showed that PO43− S2− and organic phosphorus had little effort on the removal of As (III) by the adsorbent, which does not coincide with this paper, and the reasons for this contradiction are still unclear and needs further study.