An embodiment of the invention provides an entity relationship diagram data processing system and method. The system comprises an entity relationship E-R map storage device and an E-R map processing device, wherein the entity relationship E-R map storage device is used for storing E-R maps designed and edited by a user and storing an operation type corresponding to each E-R map, and the E-R map processing device is used for acquiring the E-R maps stored by the E-R map storage device and the operation type corresponding to each E-R map, determining different types of data processing operation tasks for the E-R map according to the operation type, acquiring information needed by the different types of data processing operation tasks from the E-R maps, processing data of the acquired information according to processing rules of the different types of data processing operation tasks, and respectively storing the data processed by the different types of data processing operation tasks. Data processing efficiency in an application scene of non-design work can be improved.