[Objective] To identify some specimens of Gibellula spp. collected in China, the DELTA expert system and its function extension were performed. [Methods] The DELTA expert system was built based on 30 characters of the genus Gibellula, and then, the key, natural descriptions, distance matrix, phenetic tree and interactive automatic identification were performed. [Results] All the specimens were identified as three species as follows, respectively: Gibellula clavulifera var. clavulifera, G. leiopus and G. pulchra. [Conclusion] Based on the DELTA expert system, a database of phenotype characters and its function extension could provide a valuable information platform for the taxonomic and phylogenetic study of the genus Gibellula in the future.