Background The prevalence of being overweight and obese is increasing not just in the general population but also in individuals with intellectual disability (ID). Therefore, a need to identify factors contributing to overweight/obesity arises as this population is escalating. Materials and Methods This narrative review article summarizes pertinent research focusing on prevalence and the potential factors associated with overweight and obesity in adults with intellectual disability during the past decade. Results Prevalence of being overweight and obese among adults with intellectual disability is reportedly 28%‐71% and 17%‐43%, respectively. Factors increasing the susceptibility of being overweight or obese have been identified as female gender, increasing age, having a certain diagnosis, mild intellectual disability, as well as living independently/with family, consuming certain prescription medications, and non‐participation in physical activities. Conclusion Identification of the potential risk factors associated with being overweight and obese in this population will help tackle the challenges faced by this growing adult population with intellectual disability.