Abstract: ObjectivePCR genotyping analysis of the genetic characteristics of 74 phenotypically ungroupable Neisseria meningitidis derived from the nose and throat swabs among healthy population was conducted. MethodsPCR amplification of Neisseria meningitidis genus-specific genes, crgA and A, B, C, W135, Y, Z, X, as well as 29E of specific gene fragments of different groups, was performed to identify the genotypes of different strains. ResultsPCR amplification based on Neisseria meningitidis crgA as the target gene revealed 66 crgA-positive Neisseria meningitidis out of 74 ungroupable strains, the detection rate being 89.19%. PCR serogroup identification suggested 40 strains (60.61%) of different serogroups of genotypes among the 66 strains, including 27 strains of B group, seven of 29E group, two of X and Y each, and one of C and W135each. Conclusion PCR genotyping analsys of ungroupable Neisseria meningitidis exerted a significant epidemiologic impact on the study of Neisseria meningitidis.