A method for multiple-input multiple-output (MIMO) collaborative communication in a wireless communication system includes at least one user equipment and M base stations performing collaborative communication with the user equipment. Here, M is an integer that is greater than or equal to 2. The method includes the following processes for each user equipment: a first level of MIMO pre-coding process is performed for each base station to acquire each first level of pre-coding matrix corresponding to each base station; a second level to the X-th level of MIMO pre-coding process is performed sequentially to acquire the second level to the X-th level of pre-coding matrices of the corresponding base stations. Here, X is an integer that is greater than or equal to 2. A pre-coding device, a user equipment and a wireless communication system related to the method are also provided.