Abstract: Genomic DNA were prepared from 5 sibling species of Anopheles hyrcanus group in-eluding An. sinensis (ASS), An. anthropophagus (ALA), An. liangshanensis (ALS),An: crawfordi (ACW) and An. xiaokuanus (AXK). High molecular weight DNA from each species were cut with three restriction endonuleases (Bgl Ⅱ, Hae Ⅲ and PstⅠ) and the DNA fragments analysed by agarose gel electrophoresis and ethidium bromide st?.inin.g. Three enzymes (Bgl Ⅱ, Hae Ⅲ and PstⅠ) produced unique fragments in all sibling species tested. A diagnostic restriction fragment length of DNA from 5 sibling species of An. hyrcanus group may be derived from a single restriction enzyme pattern (i. e. Bgl Ⅱ). The results demonstrated that the restriction fragment length differences of repetitive DNA could used as a tool to distinguish sibling species of An. hyrcanus group.