Background: Adults with intellectual or developmental disability (ID/DD) have multiple risks for low bone mineral density (BMD) without formal guidelines to guide testing. We sought to identify risk factors and patterns of BMD testing among institutionalized adults with ID/DD. Methods: We evaluated risk factors for low BMD (Z-/T-score < -1) and patterns of BMD testing among adults with ID/DD receiving care at a state-run residential facility. Kruskal-Wallis, Fisher's exact and Pearson's chi-squared tests were used as appropriate. Results: Of the 140 eligible patients, only 44% ever had BMD testing of which 89% had low BMD. Median age at diagnosis was 42 years old. Individuals with low BMD were more likely to be older, non-weight bearing, Caucasian and have severe cognitive delay. Conclusions: Adults with ID/DD in this facility had a high prevalence of low BMD. Further studies are needed to better characterize risk factors and inform screening within this high-risk population.