To evaluate the etiologic role of human papillomavirus (HPV) in oral carcinogenesis, DNA samples were purified from 103 oral squamous cell carcinoma (OSCC) and 30 normal oral mucosal (NOM) specimens. A nested polymerase chain reaction, DNA sequencing, and gene-chip HPV typing were used to identify multiple HPV types in our samples. We found that the positive rates of all HPV types and of high-risk HPV types were significantly higher in OSCC samples (49.5% and 41.7%, respectively) than in NOM samples (6/30 [20%; P < .01] and 5/30 [17%; P < .05], respectively) and significantly higher in non-oral habits (OH)-associated OSCC samples (31/51 [61%] and 28/51 [55%], respectively) than in OH-associated OSCC samples (20/52 [38%; P < .05] and 15/52 [29%; P < .001], respectively). High-risk HPV types and all HPV types had odds ratios of 3.97 (P = .0097) and 3.92 (P = .006), respectively. Our results suggest that HPVs, particularly high-risk HPVs, might be associated with the development of OSCCs, especially the non-OH-associated OSCCs.