Objective To investigate the change of s-100β and glial fibrillary acidic protein(GFAP) in serum of infantile spasms(IS) and the associativity with brain damage.Methods The protein levels of s-100β and GFAP were determined by ELISA 24 hours after seizure,4 weeks and 12 weeks after medication.Results Twenty-four hours after seizure,the protein levels of s-100β and GFAP in serum of IS were significantly higher than those of control group(P0.01) ; 4ws after medication,the levels of s-100β and GFAP dropped significantly,but still had significance compared with control group (P0.01) ;12ws after medication,levels of s-100β and GFAP of ineffective group were higher than those of other groups(P0.01),there were no significance between other groups; the levels of s-100β and GFAP of IS in serum had significantly positive correlation(P0.01).Conclusion s-100β and GFAP could be early markers of brain damage after seizure of IS and could predict prognosis.