Determining protein levels in each tissue and how they compare with RNA levels is important for understanding human biology and disease as well as regulatory processes that control protein levels . We quantified the relative protein levels from over 12,000 genes across 32 normal human tissues . Tissue-specific or tissue-enriched proteins were identified and compared to transcriptome data . Many ubiquitous transcripts are found to encode tissue-specific proteins . Discordance of RNA and protein enrichment revealed potential sites of synthesis and action of secreted proteins . The tissue-specific distribution of proteins also provides an in-depth view of complex biological events that require the interplay of multiple tissues . Most importantly, our study demonstrated that protein tissue-enrichment information can explain phenotypes of genetic diseases, which cannot be obtained by transcript information alone . Overall, our results demonstrate how understanding protein levels can provide insights into regulation, secretome, metabolism, and human diseases.