A method for activating or updating a pathloss reference signal, RS, corresponding to a physical uplink shared channel, PUSCH, comprising: receiving, by a terminal device, a medium access control, MAC, control element, CE, transmitted by a network device, wherein the MAC CE comprises at least one spatial relationship information-physical uplink share channel-, SRI-PUSCH-, Power Control field and at least one pathloss RS field, and the at least one SRI-PUSCH-Power Control field is used to indicate at least one SRI-PUSCH-Power Control configuration, and the at least one pathloss RS field is used to indicate at least one pathloss RS corresponding to the at least one SRI-PUSCH-Power Control configuration; and updating or activating, by the terminal device, the at least one pathloss RS corresponding to the at least one SRI-PUSCH-Power Control configuration according to the MAC CE; characterized in that, the MAC CE comprises multiple SRI-PUSCH-Power Control fields, and the multiple SRI-PUSCH-Power Control fields correspond to multiple SRI-PUSCH-Power Control configurations configured for the terminal device one by one, and each SRI-PUSCH-Power Control field in the multiple SRI-PUSCH-Power Control fields is used to indicate whether a pathloss RS of a corresponding SRI-PUSCH-Power Control configuration needs to be updated or activated, an SRI-PUSCH-Power Control field represented as a first value in the multiple SRI-PUSCH-Power Control fields is the at least one SRI-PUSCH-Power Control field, the at least one SRI-PUSCH-Power Control field corresponds to the at least one pathloss RS field one by one, and a pathloss RS field in the at least one pathloss RS field is used to indicate an identifier of a pathloss RS in the at least one pathloss RS. receiving, by a terminal device, a medium access control, MAC, control element, CE, transmitted by a network device, wherein the MAC CE comprises at least one spatial relationship information-physical uplink share channel-, SRI-PUSCH-, Power Control field and at least one pathloss RS field, and the at least one SRI-PUSCH-Power Control field is used to indicate at least one SRI-PUSCH-Power Control configuration, and the at least one pathloss RS field is used to indicate at least one pathloss RS corresponding to the at least one SRI-PUSCH-Power Control configuration; and updating or activating, by the terminal device, the at least one pathloss RS corresponding to the at least one SRI-PUSCH-Power Control configuration according to the MAC CE; characterized in that, the MAC CE comprises multiple SRI-PUSCH-Power Control fields, and the multiple SRI-PUSCH-Power Control fields correspond to multiple SRI-PUSCH-Power Control configurations configured for the terminal device one by one, and each SRI-PUSCH-Power Control field in the multiple SRI-PUSCH-Power Control fields is used to indicate whether a pathloss RS of a corresponding SRI-PUSCH-Power Control configuration needs to be updated or activated, an SRI-PUSCH-Power Control field represented as a first value in the multiple SRI-PUSCH-Power Control fields is the at least one SRI-PUSCH-Power Control field, the at least one SRI-PUSCH-Power Control field corresponds to the at least one pathloss RS field one by one, and a pathloss RS field in the at least one pathloss RS field is used to indicate an identifier of a pathloss RS in the at least one pathloss RS.