Abstract: In order to identify the members of Anopheles dims complex of Hainan Province,an analysis of relative content of cuticular saturated n-paraffins of Anopheles dirus collec- ted from different localities and in different months in Hainan Province was performed by using gas chromatography.The difference among the cuticular hydrocarbons n-pr.raffins components was atitistically insignificant.The values of stepwise cluster analysis (Q model) were very close for all the collected populations.These data suggested that there might be are species of Anopheles dims complex which was further confirmed by the similarities bet-ween blood preference,seasonal variation,and nocturnal activity.