Aldicarb, a carbamate pesticide, is commonly used in agriculture and can be naturally degraded to metabolites, resulting in their occurrence in drinking water supplies. The disinfection process using different oxidants for the treatment of drinking water provides the opportunity to degrade aldicarb and its metabolites to byproducts that may pose more human health risk than the parent compounds. A comprehensive study of aldicarb and its metabolites involving treatment with free chlorine (FC), monochloramine (MCA), ozone (O3), chlorine dioxide (ClO2), hydrogen peroxide, permanganate (MnO4) and UV radiation was performed to identify the degradation products. Free chlorine, high-dosage UV radiation and permanganate exhibited stronger oxidation capacity than the other oxidants studied, with chlorine dioxide showing the weakest oxidation ability among them. Aldicarb sulfoxide was formed as the degradation product of aldicarb by oxidation with free chlorine, MCA, ozone, and hydrogen peroxide. Aldicarb sulfone was identified as an oxidation byproduct of both aldicarb and aldicarb sulfoxide by permanganate. N-chloro-aldicarb sulfone was formed as an oxidation byproduct of aldicarb sulfone by free chlorine. The comprehensive information is very valuable for water treatment facilities and environmental researchers.