Introduction: The primary goal of highly active antiretroviral therapy (HAART) is to reduce mortality and morbidity rates among HIV-infected people, and to improve their quality of life. As of May 2015, a total of 8, 69,576 HIV/AIDS patient are receiving free Antiretroviral Therapy (ART), in our country despite which, there has been high HIV prevalence and mortality in certain areas. The objective of this retrospective study was to determine the factors associated with mortality in patients on ART under routine programme conditions in an ART centre in Southern Odisha. Methods: Data of HIV positive patients under HAART in the ART centre during April 2014 to March 2015 time period were collected and analysed for various demographic variables, clinical profile and mortality. Results: A total of 956 patients were under HAART during the study period, of which 204 (21.33 %) expired. Even though in majority of patients who died [193 (94.6%)] ART was initiated early; only 56 (27.45%) were under regular treatment; 73 (35.8%) had missed (irregular) doses, 75 (36.8%) were lost to follow up (LFU). Majority (88.24%) of the deaths occurred in the first six months of therapy in patients who had associated tuberculosis or some other AIDs related complications. Conclusion: The study reveals poor survival during the study period in spite of no delay in ART initiation. The increasing number of missed dose cases and LFU cases early after initiation of therapy suggests immediate need to intensify the patient retrieval and counselling services in this region.