Fish Lateolabrax japonicus were exposed to anion surfactant sodium dodecylbenzene sulfonate (SDBS) and sodium dodecyl sulfate (SDS) at 1mg/l, respectively, for 6, 12 and 18d, with one control group. Liver antioxidant enzymes, including superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), reduced glutathione (GSH) and glutathione S-transferase (GST) were determined; brain acetylcholinesterase (AChE) and liver inducible nitric oxide synthase (iNOS) activities were also measured. The results of the study indicated that these parameters made different, sometimes, adverse responses to SDBS and SDS exposure, such as the activity of iNOS can be inhibited by SDBS and induced by SDS, the different physico-chemical characteristics of SDBS and SDS should be responsible for their effects on enzyme activities.