The tumor matrisome, the collection of structural and functional extracellular matrix (ECM) proteins found in tumors together with ECM-associated proteins, growth factors, cytokines and chemokines is an extremely dynamic entity whose composition and regulation depends on both local, cell-specific processes and overarching pan-cancer microenvironmental landscapes. A deeper knowledge and understanding of the tumor matrisome would grant us novel diagnostic, prognostic and therapeutic possibilities but to reach that point there is a pressing need to combine fine-grained molecular studies with system biology approaches to build a complete map of what actually happens in the tumor microenvironment. In this chapter, we will review the most salient findings on the tumor matrisome at the transcriptomics, regulomics and proteomics level and show how the use of big data enables the identification of biological features and characteristics that cross different tumors and the discovery of novel molecular mechanisms connecting the different omics level. Also, we will provide a simple walkthrough to jumpstart matrisome data analysis for complete beginners in a bid to ignite more research in this fascinating field.