The invention discloses a digital city management data sharing system based on cloud calculation, which comprises an application system and a safety function module, wherein the application system comprises a city management service module and a city management service expansion module; the application system is used for sending a safety request to the safety function module, and receives a safety processing result fed back by the safety function module at the same time; the application system sends an assistant management request to an auxiliary functional system, and receives an assistant management result fed back by the auxiliary functional system at the same time; the application system further sends a calculation request to a cloud calculation service center, and receives a calculation result fed back by the cloud calculation service center at the same time; and the safety function module is used for monitoring and maintaining safety of an operating system, a database, application software and an application system account, and alarms when discovering a potential safety hazard. By separating service processing and data processing, the digital city management data sharing system based on cloud calculation reduces the problems that the service processing unit is not familiar to system functions, service process and data processing, and is difficult in maintenance.