A distributed network-based scene surveillance radar redundancy control system disclosed by the present invention is equipped with a radar assembly, an Ethernet switch and a radar terminal. In order to enable the radar assembly to purposively and respectively select one of two servo controllers, one of two transmitter controllers, one of two receiver controllers, one of two distribution extension controllers, one of two signal processing controllers, one of two data processing controllers and one of two digital power supply controllers which have different types to from a main body frame, all controllers and the radar terminal are connected with the Ethernet switch as the nodes of the distributed network and are controlled by the distributed node control units respectively, thereby forming the distributed network. The distributed network adopts the distributed network topology structures as the star structures, and in the distributed network, the priority of the radar terminal is highest. The distributed network-based scene surveillance radar redundancy control system of the present invention has the characteristics of being simple and reliable, and being strong in extensible capability and flexible in redundancy switching control mode.