The invention discloses a method for simple data interaction between an electric power region I and an electric power region III by using reserve 1bit data of a forward direction isolating device, and relates to the technical field of data interaction of electrical power systems. The method is characterized by comprising the following steps: requiring an NAT conversion on IP of an outer net server on which a server-side software is mounted, initializing Socket at an end of the outer net server firstly, then binding with a port, listening into the port, after intranet client software receives a remote control check request, building socket connection with an outer net server-side software, and matching the equipment object unique code in a scheduling command with the equipment object unique code in a remote control constrain analysis request. The method provided by the invention is reasonable, can feedback information in time and is convenient to operate.