The invention discloses a power grid fault detection system and method. The power grid fault detection system includes a monitoring mobile terminal and a monitoring host; the monitoring mobile terminal include a WeChat module and an information sending module; the WeChat module is provided with an image acquisition unit used for obtaining image information of power grid equipment; the image sending module is used for sending the image information acquired by the image acquisition unit to the monitoring host; the monitoring host comprises an information receiving module and a display module; the information receiving module is used for receiving the image information; and the display module is used for displaying the image information. With the power grid fault detection system adopted, fault information monitoring can be carried out more conveniently and quickly, and faults can be found out in time.