The invention provides a cloud computation-based power system simulation data management method. The method comprises the following steps that 1, a foreground receives a task operating command and transmits the task operating command to a cloud simulation platform; 2, a storage server receives and stores the task operating command of a user; and 3, a computation template, which corresponds to the task operating command and is stored in a computation template storage server, is selected when the task operating command is a computation task; a computer group computes to obtain the result of the computation task according to power grid data and the computation template; and the result of the computation task is stored in the storage server, and the user acquires the result of the computation task by accessing the storage server. According to the method provided by the invention, the computation task is computed by the computer group which operates the cloud computation environment, and a large amount of computation resources are managed and cooperated by scheduling and optimizing technologies, so that the whole power grid data are integrated and computed efficiently and quickly.