The invention discloses a cloud-based power disaster recovery data security protection system and device, and a medium. The cloud-based power disaster recovery data security protection system comprises a cloud storage unit, a data collection unit, a central management unit, a data backup unit, a data calculation unit, a fault detection, analysis and processing unit, a data monitoring unit, and a fault crosstalk prevention unit. By implementing the invention, the influence on the currently running service and application is minimized, and the network units in the power system can be ensured notto influence each other, and the attack or fault is limited within a certain range.