Background: Human papillomavirus (HPV)-associated head and neck squamous cell carcinoma (HNSCC) is an evolving and growing disease, especially in developing countries. However, the clinical characteristics of HPV-associated HNSCC in regard to HPV infection rates, patient features, and prognosis are under-reported in the Asian population. Methods: In this study, we retrospectively enrolled a 400-case cohort of HNSCC with p16 immunochemistry and analyzed with long-term follow-up. We investigate the current HPV prevalence of HNSCC, unique HPV-associated patient clinical characteristics, and patient prognosis in the southern China population. Results: HPV infection exhibited a 15% prevalence in all HNSCC cases, notably higher in oropharyngeal cases (30.7%), followed by oral cavity (11.8%), laryngeal (10.1%), and hypopharyngeal (2.5%). HPV status, gender, old age, and location of tumor were significantly associated with the patient’s survival. Tonsil invasion was found more frequent in HPV-positive oropharyngeal HNSCC than in HPV-negative cases. HPV-associated HNSCC patients tend to possess stronger tobacco and alcohol habits, which were correlated to poor survival. HPV status’s correlation with gender, age, and anatomical location is associated intricately with patient survival. The secondary primary tumor rate was found higher within the HPV-negative group, compared to the HPV-positive group (9.12% versus 1.67%). Conclusion: Our study provided a current picture of HPV-associated HNSCC in the southern China population and elaborated the understanding of key factors that correlate to HNSCC prognosis. Our findings indicated a strong susceptibility of HPV-associated oropharyngeal HNSCC in the tonsil and the difference in secondary primary tumor rates associated with HPV status.