Abstract: Purified bentonite was modified with sulfuric acid in this paper.Then the suitable condition of removing pb²⁺ by acid-modified bentonite was studied.The results show that when the initial concentration of pb²⁺ is 10mg/L,the removal ratio of pb²⁺ by acid-modified bentonite can reach greater than 99.6% under the following condition: the dosage of acid-modified bentonite is 8g/L,pH=7,the stirring velocity is 180r/min,the adsorption time is 15mins.The residual concentration of pb²⁺ is less than the national effluent concentration limit after the treatment by acid-modified bentonite.The efficiency of treatment was still satisfying after the used acid-modified bentonite was regenerated and reused.This research provides valuable date for bentonite's modification and its application in treating heavy metal wastewater.