The invention relates to a mobile robot type high voltage switch cabinet swarm intelligent online monitoring system and method for monitoring a high voltage switch cabinet swarm in a switch room. Themonitoring system comprises a monitoring host, a sensing module, a moving track and a track controller; the sensing module includes a partial discharge intelligent sensor; the moving track is disposedin the switch room, and is connected to the track controller; the partial discharge intelligent sensor is slidably disposed on the moving track, and communicates and interacts with the monitoring host through a wireless network; and the monitoring host is connected to the sensing module and the track controller. Compared with the prior art, the invention can reduce the monitoring cost, has high diagnostic reliability, and can avoid difficulty in field wiring.