Abstract: Objective To investigate the effect of microwave radiation on expressions of synaptic associated proteins: synapsin I,VAMP-2,syntaxin and synaptophysin.Methods 25 Wistar rats were exposed to microwave which average power density was 30 mW/cm².Western blot was used to study the change of the expressions of synapsin I,VAMP-2,syntaxin and synaptophysin of synaptosome in cerebral cortex and hippocampus,and immune co-precipitation was used to study the interaction of VAMP-2 and syntaxin.Results It resulted in the decrease of synapsin I at after 3-day radiation in cerebral cortex (P<0.01),but increase at 1 d,decrease at 3 d and increase at 7 d in hippocampus(P<0.01);the increase of synaptophysin at 1～7 d and decrease of VAMP-2 and syntaxin at 6 h～7 d after radiation in cerebral cortex and hippocampus(P<0.01); the decrease of the interaction of VAMP-2 and syntaxin at 3 d in cerebral cortex and at 6 h～7 d in hippocampus after exposure(P<0.01).Conclusion Microwave radiation can induce the abnormity of expressions of synaptic associated proteins in cerebral cortex,and hipoccampus then induce the disorder of synaptic transmission.