A sidelink communication method, a communication apparatus, and a communication system are provided, to perform sidelink communication configuration in a relay scenario. The method includes: A remote device sends first information to a relay device; the relay device receives the first information from the remote device, where the first information includes a first paging parameter of the remote device; the relay device sends second information to a first network device, where the second information includes the first paging parameter; the first network device receives the second information from the relay device; and the first network device performs sidelink configuration based on the second information. In this way, the first network device performs sidelink communication configuration based on the first paging parameter, so that quality of sidelink communication between the relay device and the remote device is improved, and scheduling flexibility of the first network device is improved.