Background: Promotion of a healthy lifestyle for people with intellectual disabilities is important; however, the effectiveness of lifestyle change interventions is unclear. Aims: This research will examine the effectiveness of lifestyle change interventions for people with intellectual disabilities. Methods and Procedures: Randomized controlled trials (RCTs) of lifestyle change interventions for people with intellectual disabilities were included in a systematic review and meta-analysis. Data on study and intervention characteristics were extracted, as well as data on outcome measures and results. Internal validity of the selected papers was assessed using the Cochrane Collaboration’s risk bias tool. Outcomes and Results: Eight RCTs were included. Multiple outcome measures were used, whereby outcome measures targeting environmental factors and participation were lacking and personal outcome measures were mostly used by a single study. Risks of bias were found for all studies. Meta-analysis showed some effectiveness for lifestyle change interventions, and a statistically significant decrease was found for waist circumference. Conclusion and Implications: Some effectiveness was found for lifestyle change interventions for people with intellectual disabilities. However, the effects were only statistically significant for waist circumference, so current lifestyle change interventions may not be optimally tailored to meet the needs of people with intellectual disabilities.