Abstract: The present invention relates to network management and discloses a system, method, and device for Automatic Protection Switching (APS). The system includes a sending device and a receiving device. The sending device includes a first sending line card and a second sending line card. The receiving device includes a first receiving line card and a second receiving line card. In the embodiments of the present invention, the first receiving line card and the second receiving line card check arrival of continuity check messages, and perform centralized switching control on the line cards automatically according to the check result, thus improving APS efficiency and reliability of a PS-based transport network.