The utility model discloses a real-time evaluating and state monitoring system for an automatic communication network of a transformer substation. The system comprises at least two backbone network switches arranged inside the transformer substation. The system is characterized by being deployed in a bypass mode compared with an integrated automation system of an conventional transformer substation and comprising a real-time data acquisition platform, an on-line protocol analysis system and a terminal analysis system which are arranged inside the transformer substation and a unified management system arranged inside a dispatching center; and the transformer substation is connected with the dispatching center by a 2M optical fiber channel through an EI network bridge. The system can be used for monitoring network performance indexes and network traffic in a real-time manner and intelligently resolving communication protocols of an automatic system of the transformer substation and can realize a real-time alarm function, so that manageability, stability and reliability of the automatic communication network of the transformer substation are improved, beforehand prevention can be realized, and possibility of accidents is decreased.