BackgroundWith the rise of artificial intelligence (AI) technologies in recent years, the rapidly expanding fields of AI-supported chatbot lifestyle interventions have offered new solutions to the global epidemic of physical inactivity and obesity. However, to the best of our knowledge no systematic review of chatbot-based lifestyle change intervention exists. The goals of this systematic review are to summarize the characteristics of chatbot interventions and to synthesize and evaluate uses of chatbots to improve physical activity, dietary, and weight management behaviors and to identify knowledge gaps and directions for future studies.MethodsIn collaboration with a medical librarian, six electronic bibliographic databases (PubMed, EMBASE, ACM Digital Library, Web of Science, PsycINFO, and IEEE) will be searched to identify all relevant studies. Main outcomes include changes in self-report and/or objectively measured physical activity, sedentary behavior, diet, and body weight. Additional outcomes include feasibility, acceptability, safety, and user satisfactions of chatbots. Two reviewers will independently screen the title and abstract, conduct a full-text screening to select the qualified studies, extract data from the included studies, and assess the risk of bias using Covidence software. Lastly, we will conduct a qualitative synthesis of the findings. However, if several randomized controlled trials that report similar outcome measurements are identified., quantitative synthesis will be provided.DiscussionTo the best of our knowledge, this is the first systematic review to synthesize and evaluate the existing research that assess the impact of AI chatbots on changing physical activity, dietary, and weight management behaviors. We anticipate our findings to advance knowledge by identifying the key characteristics of effective AI chatbot interventions and by highlighting knowledge gaps and limitations in the literature.Systematic review registrationInternational Prospective Register of Systematic Reviews (PROSPERO): CRD42020216761.