A service processing method and system, and a device to reduce a large quantity of back end servers, and to simplify a structure of a distributed system where the method includes receiving, by a master device in a resource pool, a service processing request, determining, by the master device, a resource required by a service, determining, according to a remaining resource of each slave device in the resource pool, a slave device that satisfies the resource required by the service, and assigning, by the master device, the service to the corresponding slave device for processing, where the master device and the slave device are both video surveillance front end devices, and the master device determines a device that is in the front end devices and whose remaining resource satisfies a preset threshold as the slave device.