Disclosed herein are an apparatus and method for data compression and decompression based on calculation of an error vector magnitude. A data compression apparatus includes a lossy compression unit for calculating, in advance, a reference error vector magnitude depending on lossy compression and decompression by removing lower bits from a data signal composed of bitstreams, for setting removal target lower bits satisfying a preset error vector magnitude requirement, and for lossily compressing the data signal by removing the removal target lower bits from the data signal, and a communication unit for transmitting the compressed data signal to a data decompression apparatus.