Individuals with HIV are at increased risk for osteoporosis and fracture. Using the Health Beliefs Model, we identified key relationships between knowledge, self-efficacy and health beliefs pertaining to physical activity and dietary calcium intake, two key modifiable preventive measures for osteoporosis. Individuals with HIV are at increased risk for osteoporosis and fracture. Few studies have systematically explored concerns related to osteoporosis prevention among this group. Applying the Health Beliefs Model (HBM), we examined associations between osteoporosis-related preventive health behaviors (i.e., physical exercise and dietary intake) and knowledge, self-efficacy and health beliefs in a large cohort of Chinese individuals with HIV. We conducted a cross-sectional study with participants from an ongoing multi-center trial. Volunteers completed a questionnaire consisting of the International Physical Activity Questionnaire (IPAQ), a calcium and vitamin D intake assessment, the Osteoporosis Knowledge Test, Osteoporosis Self-Efficacy Scale, Osteoporosis Health Beliefs Scale, and relevant sociodemographic and clinical risk factors. A total of 263 of 297 eligible participants enrolled in this study. Mean age of participants was 38.4 ± 9.8 years, average BMI was 21.6 ± 2.6 kg/m(2), and 76 % were men. About 30 % of the sample reported low physical activity. Consumption of foods from each calcium and vitamin D-rich category averaged between multiple times per month to weekly. Knowledge regarding osteoporosis was universally low and self-efficacy correlated directly with engagement in preventive behaviors. Women and individuals with lower education perceived greater barriers to adopting preventive behaviors. Multivariate logistic regression adjusted for age, sex and BMI showed that calcium and vitamin D intake was directly correlated with knowledge and self-efficacy, whereas physical activity correlated with manual labor occupation, perceived barriers to exercise and health motivation. Behavioral frameworks such as the HBM may provide important insight into promoting adoption and maintenance of osteoporosis-related preventive behaviors among individuals with HIV.