Abstract: JPEG has been widely used so far.As a generic compression algorithm for the static images，JPEG is too complex to be suitable under some circumstances.Based on the analysis of the principles of JPEG，by improving the quantization module and the coding module of JPEG，a simple compression algorithm based on discrete Cosine Transform（DCT） is proposed.The proposed algorithm shows good compression performance for low compression ratio applications，the compression ratio is lower than 15，while it is much simpler than JPEG.