Abstract: Objective: To study the effects of taurine on diaphragm injury in diabetic rats.Methods: Twenty-four SD rats were randomly divided into normal control(NC) group,diabetic(DM) group and taurine treatment(Tau) group.DM group and Tau group rats were given streptozocin(STZ) 50 mg/kg intraperitoneal injection.NC group and DM group rats were treated with watar,Tau group rats were treated with 1% taurine in drinking watar.After 4 weeks,the body weight(BW) and level of blood glucose(BG) were measured.Superoxide dismutase(SOD),nitric oxide synthase(NOS) activities and malondialdehyde(MDA),NO contents in diaphragm tissues were also measured.The ultrastructure of diaphragm were intvestigated by electron microscope.Results: SOD,NOS activities,NO contents were significantly lower(P<0.01),BG and MDA content were significantly higher in DM group(P<0.01).Compare with DM group,SOD,NOS activities and NO contents were higher(P<0.05 and P<0.01),BG and MDA content were lower in Tau group(P<0.01).The ultrastructure under electron microscope indicated that in DM group diaphragm fibres fracture,mitochondrions swelling and degeneration.The above changes were inhibited by treatment of taurine.Conclusions: Taurine can increase SOD,NOS activities,NO contents and decrease MDA conten in diabetic diaphragm.