The invention discloses a substation environment monitoring simulation device, a system and a method. The device is matched with a gateway machine and a rotating ring subsystem simulator for realizing environment signal acquisition simulation and equipment control simulation in the rotating ring subsystem simulator. The device comprises multiple first communication modules, a data and command processing module, a protocol conversion module, and a second communication module. According to the substation environment monitoring simulation device, interconnection and intercommunication between the substation environment monitoring simulation device and all equipment in the rotating ring subsystem simulator and communication between the substation environment monitoring simulation device and the gateway machine are realized, functions of acquisition of various signals and equipment control simulation are provided, real environment signals of the substation can be simulated, the complex degree of an actual test can be reduced, the lab space is saved, the cost is reduced, and quick development of an unattended intelligent substation can be promoted.