The present disclosure relates to a cell multicast service processing method and a device. The method may include receiving, by a first base station, a multicast service session start message sent by a multicast coordination entity. The method may also include sending, by the first base station, a multicast service session start failure message or a multicast service session start response message to the MCE, where the multicast service session start failure message indicates that a multicast service fails to be started for all the cells that are managed by the first base station and for which a multicast service session is to be started, and the multicast service session start response message includes an identifier of a cell for which a multicast service is successfully started among the cells that are managed by the first base station and for which a multicast service session is to be started.