The invention discloses a gray release method for an IOM system, and the method comprises the steps: releasing a new version into a gray environment, detecting whether an online service of the new version is normal, and releasing the new version into an original production environment when the online service of the new version is detected to be normal, thereby finishing the release of the new version. According to the invention, barriers between a production environment and a test environment are mainly eliminated, including different environments, different configurations, different codes andthe like, so that a new version can be published on line for verification earlier than before. According to the invention, version upgrading can be flexibly carried out. A certain release risk is avoided, and the influence range of product iterative upgrade is reduced; Feedback suggestions of a user are rapidly obtained, product functions are perfected, and product quality is improved. Inconvenience brought to a user due to outage release is avoided, package sending at night is not needed, and operation and maintenance and the working time of developers are more rational. The method has a disaster recovery capability, and reduces the risks of server crash, system interface abnormity and the like caused by full release.