The invention belongs to the technical field of automatic control, and aims to solve the technical problem of providing a network topology device and method for a control station and an instrument control system which are high in communication rate and high in reliability. The device comprises Ethernet and buses, wherein the Ethernet is arranged among cases and is used for transmitting request signals and answering signals between a communication node of a main control case and communication nodes of other cases; and the buses are arranged in the cases and are used for transmitting communication data between the communication node of the main control case or the communication nodes of other cases and a corresponding input/output card piece. Therefore, an Ethernet technology can be combined, a communication speed is high, the field buses have the characteristics of simplicity for wiring and flexibility for expansion, and the advantages of the Ethernet technology and the field buses are sufficiently played.