Abstract: Objective To reveal the pathogen of hand-foot-mouth disease(HFMD)and to know the main virus type in anoutbreak of HFMD in Hainan province in 2008.Methods According to the Hand-foot-mouth disease control and prevention guide(2008)issued by Health Ministry,the nucleic acids from specmiens such as nasal and throat swabs,anus swabs,herpes fluid of clinical diagnosed cases of HFMD were isolated.The RNA was amplified by reverse transcription-polymerase chain reaction(RT-PCR)usingenterovirus universal prmie,renterovirus type 71 prmier and coxsackie virus group A type 16 prmier.Results Among 274 clinically diagnosed cases,EV 71 virus RNA was positive in 102 cases,CoxA16 virus RNA in 12 cases,and other entero virus RNA in 35 cases.The RNA testing positive rate of the herpes fluid was 72.0%,with a positive rate of 40% for anus swabs and 34.8% for nasal and throat swabs.The RNA of 54 specmiens detected directly by RT-PCR was negative.But these specmiens inoculated to RD cell line showed cytopathic effect and were identified by RT-PCR.The results showed that enterovirus RNA was positive in 48 specmiens(88.89%).EV 71 RNA was positive in 29 specmiens(53.7%);CoxA 16 RNA was positive in 4 specmiens(7.4%).Both EV 71 RNA and CoxA 16 RNA were positive in 1 specmien.Conclusion The major pathogen of HFMD was EV 71 causing the outbreak in Hainan province in 2008.CoxA 16 was one of the pathogens.The etiology surveillance of HFMD should bestreng thened in order to know the change of virus type and the trend of to xicity change.