Disclosed is a method for implementing air interface synchronization. The method includes that: a source cell performs signalling interaction with a target cell, and determines whether to be switched off or not according to a signalling interaction result. A content about which the source cell performs signalling interaction with the target cell includes at least one of: on/off state information of the source cell, on/off state information of the target cell, whether the target cell finds a new synchronization source or not, timing at which the source cell enters an off state, candidate synchronization source cell set information of the target cell and associated affiliated target cell information of the target cell. The present disclosure further discloses a cell and system for implementing air interface synchronization.