The invention discloses a data caching method in a disconnection state of the distributed application of a power dispatching automation system, which is characterized by comprising the following steps of: (1) circularly detecting whether the application of a local system operates in the disconnection state or not by a system operating state detection module, continuously detecting if conditions are not met, and starting a data caching module after the conditions are met, wherein the data caching module includes a historical sampling data caching module, a historical alarm record caching module and a manual operation data caching module according to different caching data types; (2) caching plant station data administrated in a disconnection area, and generating a historical sampling data file; (3) increasing a disconnection label in the content of alarm information during disconnection, and generating a historical alarm record into a data file; and (4) caching various operation information into a local real-time library by adopting different storage modes through the manual operation data caching module. The invention can effectively prevent the loss of system application data during the disconnection, thereby ensuring the integrity of the data.