The application provides a method, network equipment and a system for managing network slice instances, so as to improve the efficiency of managing the network slice instances. The method comprises the following steps: the first network equipment determines that configuration parameters of a first network slice subnet instance need to be modified, and the first network equipment is used for managing the first network slice subnet instance; the first network equipment modifies the configuration parameters of the first network slice subnet instance; the first network device sends report information to a second network device, wherein the report information is used for indicating a result of modifying the configuration parameters of the first network slice subnet instance, the second network device is used for managing the first network slice instance, and the first network slice instance comprises the first network slice subnet instance.