Disclosed are a powering off and rebooting method, apparatus and system. Wherein, the method includes: an office-end device monitoring a user-end access device; and when the office-end device monitors that the user-end access device is halted, sending a reboot command to the user-end access device; wherein the reboot command is used for indicating a power supply module in the user-end access device to perform a powering off and rebooting operation on the user-end access device. The abovementioned solution solves the problem in the related art that technical personnel have to go to the site to reboot a device if the software reset is invalid when the device is halted, so that research and development technical personnel can timely and easily power off and reboot the device without going to the site, thus treating a failure timely and reducing maintenance costs, and improving the operability and maintenance efficiency of maintenance personnel.