The embodiment of the invention provides coding and decoding method and device, a communication system, a mobile terminal and a base station, wherein the receiving data comprises business data of business data parameter information and soft information; the soft information comprises information bit data, first check bit data and second check bit data; the column parameters in an information bit interwoven matrix and a check bit interwoven matrix during rate matching are obtained according to the business data parameter information; and the soft information is filled into the corresponding matrix after rate de-matching according to the column parameters of the obtained information bit interwoven matrix and the check bit interwoven matrix and a column interwoven list. The invention also provides the corresponding device, the communication system, the mobile terminal and the base station. The method, the device and the system can reduce the complexity of the information processing in the course of rate de-matching.