To evaluate the periodontal status of HIV seropositive patients and to find out if any correlation exists between the severity of periodontal disease and the CD4 cell count in HIV patients. One hundred and thirty patients attending the Viral Diseases OPD, Calcutta School of Tropical Medicine, Kolkata were examined. They were grouped according to the CD4 cell count as Group A – Subjects with CD4 Cell count < 200/μL and Group B – Subjects with CD4 Cell count≥200/μL. Their community periodontal index of treatment needs (CPITN) score were recorded. It was found that most of the patients in each group were having score ‘2’ (i.e. presence of supra or subgingival calculus), as their highest score. A statistically significant association was found between immune status as depicted by CD4 cell count and periodontal status as shown by highest CPITN score in the present study. The present study confirms the effect of immunosuppression on periodontal diseases in HIV infected patients.