【Background】 Liriomyza sativae Blanchard (Diptera: Agromyzidae), an invasive alien species, is an important pest on many vegetables, flowers, tobacco, and cotton in many agricultural areas in China. Morphological identification of L.sativae is limited by small size, the high degree of similarity to related species and polymorphism. In this study, a method was described for the development of DNA marker for the identification of L.sativae. 【Method】A pair of speciesspecific PCR (SSPCR) primers based on a fragment of known mitochondrial DNA cytochrome oxidase I (mtDNA CO[KG-*2]Ⅰ) sequence (936 bp, GenBank accession no.[KG-*8]: EU219613) was designed for L.sativae. 【Result】 The SSPCR primers amplified a single band of 294 bp of L.sativae. The specificity of the primers was validated using four other leafminer species, including Liriomyza huidobrensis (Blanchard), Liriomyza trifolli (Brugess), Liriomyza chinensis (Kato) and Phytomyza horticola Goureau, all of them commonly occurring in China. All L.sativae specimens were correctly identified, and no crossreactions with other leafminer species were observed. The method was tested on single individuals in the egg, first, second and thirdinstar larvae, pupa and adult (male and female) stages, and proved to be applicable for all life stages. Moreover, the 294 bp mtDNA fragment could be clearly identified even at the dilution as low as 1/3840 of a whole female adult of L.sativae. 【Conclusion and significance】 The SSPCR method developed is promising, effective, fast and economic identification, hence proposed as a valuable alternative to traditional identification of this insect species. This technique should be applicable in quarantine testing for L.sativae during transportation of seedlings of flowers and vegetables and also in monitoring and management of this insect pest.