Embodiments of the present invention relate to the field of wireless communications, for use in optimizing a data compression solution. Disclosed are a method and device for data compression, transmission, and decompression. In the present method, data-to-be-transmitted is grouped by a transmitting end, and for each group: a shift factor is determined on the basis of the most significant bit of sample data of the greatest value in the group when a sign bit is removed, data bits of the sample data in the group are leftward shifted on the basis of the shift factor; the leftward shifted sample data respectively are quantified, thus making the bit number of the quantified sample data to be equal to a target bit number for compression; the shift factor and the quantified sample data are transmitted to a receiving end, the sample data respectively are dequantified, data bits in the dequantified sample data are rightward shifted respectively on the basis of the shift factor, and decompressed sample data is acquired. Employment of the present application optimizes data compression performance.