OBJECTIVE To evaluate the prevalence rates of human cytomegalovirus(HCMV) and Epstein-Barr virus-1(EBV-1) in subgingival plaque and analyze the relationship between herpesviruses, periodontal pathogenic bacteria and periodontal clinical parameters in Chinese patients with aggressive periodontitis(AgP). METHODS A total of one hundred and twenty subgingival plaque samples were collected from 89 AgP patients and 31 healthy subjects. HCMV and EBV-1 were detected using nested polymerase chain reaction(PCR).Contemporaneously, 8 periodontal pathogenic bacteria including Actinobacillus actinomycetemcomitans(Aa), Porphyromonas gingivalis(Pg), Tannerella forsythensis(Tf), Prevotella intermedia(Pi), Campylobacter rectus(Cr),Fusobacterium nucleatum(Fn), Treponema denticola(Td), Prevotella nigrescens(Pn) were detected by 16S rRNA based PCR. RESULTS HCMV was more frequently detected in AgP patients (43.8%) than in healthy controls (12.9%, P<0.01). The prevalence rates of HCMV and EBV-1 in AgP patients with 6-8 kinds of bacteria detected were 54.4% and 17.4%, respectively, significantly higher than those with 3-5 kinds of bacteria detected (P<0.05). CONCLUSIONS The prevalence rates of HCMV and EBV was higher in AgP patients than in healthy controls. Herpesviruses and periodontal pathogenic bacteria may cooperate synergistically in the development of AgP, which could be considered as a pathogenetic consortium in future investigation of periodontaltitis.