Introduction: Despite a high burden of traffic injuries, effective integrated or linked injury surveillance systems are rarely available in many low-and middle-income countries (LMICs). The aim of the current study was to define a conceptual model for developing a national integrated traffic injury registry in Iran. Methods: A mult-method study financially and technically supported by the World Health Organization, Iranian Ministry of Health, Iranian Traffic Police, and the Iranian Legal Medicine Organization was conducted. A theoretical framework, forming the core conceptual components, was developed based on expert reviews. The preliminary conceptual model was developed by a panel of experts and tailored through a national workshop of 50 scientists, authorities and experts from nearly all sectors related to road safety promotion and injury management. It was then sent out to external reviewers in order to assess and improve the content validity of the model. Results: The conceptual model was developed to have six components. These included 1) aims and core definitions; 2) content and core measurements; 3) data flow; 4) data collection routines; 5) organizational matrix; 6) implementation organization. The Haddon's matrix was adapted to be used as the theoretical framework in defining the content and data flow components of IRTIR. Five subcomponents were defined in the content and core measurements component with each having several subcategories. Each subcomponent/subcategory was finally divided into several item groups to guide defining the final data measurement variables. The data flow component was defined with six data sequence stations. Through the organizational matrix component, five major organizations relevant to road traffic safety were defined as core data production contributors. Some organizations also owned several sub-organizations which contributed in this regard. Conclusion: It is concluded that the IRTIR conceptual model includes the required six components for developing a national integrated registry for Iran. Its main component called, content and core measurements, leads the researchers in developing final data collection tools in developing the national registry of road traffic injuries in Iran.