Moderate correlations between transcriptome and proteome were found in most studies. According to different data types, current studies could be divided into four categories. They are comparison on single point, comparison between two differential points, comparison among multiple time-sequence points and comparison among multiple non-time-sequence points. In addition to the experimental error and the different datasets, the post-transcription restriction and regulatory would affect the correlation very much. Different results might be got for the different genes, cells, organs, organisms and even the different developmental phases. Because of the differentia and complementary between them, parallel studies of transcriptome and proteome trended to be performed, which could get the panorama screen of gene expression and discover the genes regulated in post-transcription.