We sampled indicator species by carrying on biobitz to evaluate the ecological health at Bailu Park, Suzhou and identifying species by PCR, Sanger sequencing and Nanopore sequencing. The outcome indicates Bailu Park suffers from a lack of even and diverse distribution of species. Only 7 genera in Lepidoptera with close evolutionary relationships were observed and they were distributed in a narrow and restricted range,which was caused by uneven distributed nectar plants and host plants and lack in their diversity. Whether Walbachia endosymbiont infection was a factor remained to be discussed.