A communication method for monitoring and managing a network slice instance on a granularity of a tenant, comprising: receiving, by a first network management unit (900, 1100), a network component notification message sent by a second network management unit (1000, 1200), wherein the network component notification message carries tenant service instance information and status information of a network component, the tenant service instance information is corresponding to the status information of the network component, and the status information of the network component comprises network component fault information and/or network component performance information; and determining (S302, S505), by the first network management unit (900, 1100), status information of the network slice instance based on the network component notification message, wherein the status information of the network slice instance is corresponding to the tenant service instance information, and the network slice instance comprises the network component, wherein before the receiving, by the first network management unit (900, 1100), the network component notification message sent by the second network management unit (1000, 1200), the method further comprises: sending, by the first network management unit (900, 1100), network component subscription information to the second network management unit (1000, 1200), wherein the network component subscription information comprises a statistical granularity, and the first network management unit (900, 1100), using the network component subscription information, instructs the second network management unit (1000, 1200) to report the status information of the network component based on the statistical granularity, wherein the statistical granularity comprises at least one of the following: a network slice instance granularity, a network slice subnet instance granularity, and a tenant service instance granularity. receiving, by a first network management unit (900, 1100), a network component notification message sent by a second network management unit (1000, 1200), wherein the network component notification message carries tenant service instance information and status information of a network component, the tenant service instance information is corresponding to the status information of the network component, and the status information of the network component comprises network component fault information and/or network component performance information; and determining (S302, S505), by the first network management unit (900, 1100), status information of the network slice instance based on the network component notification message, wherein the status information of the network slice instance is corresponding to the tenant service instance information, and the network slice instance comprises the network component, wherein before the receiving, by the first network management unit (900, 1100), the network component notification message sent by the second network management unit (1000, 1200), the method further comprises: sending, by the first network management unit (900, 1100), network component subscription information to the second network management unit (1000, 1200), wherein the network component subscription information comprises a statistical granularity, and the first network management unit (900, 1100), using the network component subscription information, instructs the second network management unit (1000, 1200) to report the status information of the network component based on the statistical granularity, wherein the statistical granularity comprises at least one of the following: a network slice instance granularity, a network slice subnet instance granularity, and a tenant service instance granularity. sending, by the first network management unit (900, 1100), network component subscription information to the second network management unit (1000, 1200), wherein the network component subscription information comprises a statistical granularity, and the first network management unit (900, 1100), using the network component subscription information, instructs the second network management unit (1000, 1200) to report the status information of the network component based on the statistical granularity, wherein the statistical granularity comprises at least one of the following: a network slice instance granularity, a network slice subnet instance granularity, and a tenant service instance granularity.