Background: Human Immunodeficiency Virus (HIV) and Tuberculosis (TB) co-infection is a lamentable medical phenomenon and CD4 count among them is a surrogate marker of their immune status.Objectives: 1. To study the epidemiological profile of HIV –TB co-infected subjects. 2. To study the CD4 count status among HIV, TB and HIV-TB co-infected patients both at diagnosis (pre treatment) and after initiation of treatment. Methodology: This was a hospital based comparative cross-sectional study conducted at Agartala Government Medical College between May & June 2013, among 60 patients in each group of HIV, TB and HIV-TB co-infected patients. Results: The study revealed that the HIV-TB co infection and HIV infection was more prevalent among males and in the age group of . Majority of the HIV-TB co-infected patients had CD4 count less than 200 cells/μl at the time of diagnosis and there has been a significant rise in CD4 count level with the initiation of treatment in all the three groups of HIV +ve patients, HIV-TB co-infected patients, and TB patients (P value <0.00). Conclusion: Sustained efforts are needed to detect and treat tuberculosis among HIV infected patients to curb the dual menace of HIV-TB epidemic.