Objectives: It is critical to assess community readiness (CR) when implementing childhood obesity prevention programs to ensure their eventual success and sustainability. Multiple tools have been developed based on various conceptions of readiness. One of the most widely used and flexible tools is based on the community readiness model (CRM). This study aimed to adapt the CRM and assess the validity of a community readiness tool (CRT) for childhood obesity prevention programs in Iran. Methods: A Delphi study that included 26 individuals with expertise in 8 different subject areas was conducted to adapt the CRM into a theoretical framework for developing a CRT. After linguistic validation was conducted for a 35-question CR interview guide, the modified interview guide was evaluated for its content and face validity. The quantitative and qualitative analyses were performed using Stata version 13 and MAXQDA 2010, respectively. Results: The Delphi panelists confirmed the necessity/appropriateness and adequacy of all 6 CRM dimensions. The Persian version of the interview guide was then modified based on the qualitative results of the Delphi study, and 2 more questions were added to the community climate dimension of the original CRT. All questions in the modified version had acceptable content and face validity. The final CR interview guide included 37 questions across 6 CRM dimensions. Conclusions By adapting the CRM and confirming linguistic, content, and face validity, the present study devised a CRT for childhood obesity prevention programs that can be used in relevant studies in Iran.