Disclosed is a redundant hot standby control system including K industrial personal computers, with a plurality of virtual control devices being established thereon respectively, at least one of the plurality of virtual control devices being established on each IPC as a main control device; and the other virtual control devices being standby control devices. Each of the standby control devices corresponds to a virtual control device, which serves as the main control device on another IPC, except for the IPC to which the standby control device itself belongs. A procedure, which is the same as that operated on the main control device corresponding thereto, is operated on the standby control device. A control bus of the system is used for connecting a plurality of the M IPCs; and a field bus is used for connecting the M IPCs and a plurality of field devices.