To characterize the resistance of the novel rice mutant ALS¹⁷⁹ to acetolactate synthase （ALS） inhibiting herbicides， this study analyzed the Ethyl Methyl Sulfone （EMS）-mutagenized novel rice mutant ALS¹⁷⁹， together with wild-type Huahang31 （HH31）， imidazolinone-tolerant rice ALS⁶²⁷ mutant， treated by four types of ALS-inhibiting herbicides by either seed coating or seedling spray treatment at different concentrations. The phenotypes and enzyme activity indexes were further determined to investigate the resistance of the mutant ALS¹⁷⁹. The results showed that the mutant ALS¹⁷⁹ showed various degrees of resistance to benensulfuron， imazethapyr， bispyribac-sodium and pyroxsulam after herbicide coating for seed soaking and seedling spraying， and the activities of acetolactate synthase， peroxidase， catalase and superoxide dismutase tended to decrease with increasing herbicide concentration. The enzyme activities of acetolactate synthase， superoxide dismutase， catalase， and peroxidase were higher in ALS¹⁷⁹ than in wild-type HH31 under all treatment conditions， except for imidazoleisonicotinic acid treatment condition at high concentration where the enzyme activities of catalase and peroxidase were lower than those of wild-type HH31.Collectively， we found that the Ala179Val mutation conferred broad-spectrum resistance to ALS-inhibiting herbicides and provided genetic germplasm resources for the subsequent breeding of ALS-inhibiting herbicide broad-spectrum resistant rice lines.