Neisseria gonorrhoeae strains are susceptible to fluoroquinolones, and selected fluoroquinolones are recommended as primary therapy for uncomplicated gonorrhoea. However, fluoroquinolone treatment failures associated with resistance to these agents and the emergence of strains with decreased susceptibilities to fluoroquinolones have been reported. Recently, the mechanisms of quinolone resistance in N. gonorrhoeae have been identified and characterized. The alteration of the GyrA subunit of DNA gyrase has a central role in conferring fluoroquinolone resistance on N. gonorrhoeae strains, while the change of the ParC subunit of topoisomerase IV has a complementary role. Serotypic characterization studies have demonstrated that the majority of the strains with decreased susceptibilities to fluoroquinolones isolated from different regions around the world are distributed in various serotypes in serogroup WII/III. However, there have been no studies reporting the relationship between serological classification and alterations in GyrA and ParC proteins in quinolone-resistant isolates of N. gonorrhoeae. In this study, we serotyped 31 isolates with quinolone-resistance-associated alterations in GyrA and ParC proteins to assess whether alterations in these proteins were associated with one or various clones in the gonococcal population.