Background & Aim: Development of an integrated health information system in order to prioritization of needs, sources devoting, diseases surveillance detecting and early responding is very important. Therefore, this comparative study has been done about natural disaster health information systems in Iran, Japan, and U.S.A in 2005. The aim is to provide logical proposes to reinforce for developing the Iranian natural disaster health information system.

Methods & Materials: This is a descriptive and comparative study that was accomplished in form of cross sectional survey. The data was extracted from literature, papers, Iranian & foreigner journals, e-mails and other related document.

Results: Natural disaster health information system in U.S.A illustrates that there is integration and consistency between responsibilities and roles are played between involving organizations and entities. The required data for natural disaster health information system collected through National Electronic Disease Surveillance System, Pulse Net, Bio Watch, Bio Net, Syndromic Surveillance System, and “the American Red Cross-Centers for Disease Control and Prevention health Impact Surveillance System” in U.S.A and Early Estimation System and Emergency Measures Support System in Japan and Diseases Surveillance in Iran. However, in spite of U.S.A and Japan there is no classification system in Iran.

Conclusion: According to the results, Iranian natural disaster health information system can be improved by using of different data gathering methods, systems and soft wares, also applying of geographical information system and establishing health and natural disaster network and using of classification of diseases advised to up grade natural disaster health information system for Iran.