Effective antiretroviral therapy has transformed HIV infection into a chronic disease. The emphasis is now on the management of the consequences of life-long treatment and associated toxicities, including osteoporosis and fragility fractures. There is a paucity of data on HIV-associated osteoporosis in Ireland. Aims: The study aims to investigate the prevalence and relevant risk factors for HIV-associated osteoporosis. Methods: A cross-sectional study of 146 HIV-positive patients from two different tertiary referral hospitals in Dublin was employed. Results: The prevalence of osteopenia and osteoporosis of the hip and/or lumbar spine was 53.4 and 9.6%, respectively. We found significant association between decreased hip bone mineral density (BMD) and increasing age, male gender, cigarette smoking, ethnicity, intravenous drug use and lower nadir CD4. A low BMI was the single most important independent predictor of reduced BMD in our study cohort. Conclusion: Low BMD affects a large proportion of HIV-positive patients in Ireland. Our results suggest that BMD screening, monitoring and treatment (if indicated) should be considered in all HIV-positive patients.