Biofuels derived from plant cell wall lignocellulose have the potential to serve as an alternative source of energy, relieving dependence on finite petroleum reserves and reducing production of climate-changing greenhouse gases. To better elucidate cell wall structure, the plant research community has developed databases to host the accumulated information on plant cell wall-related enzymes. The goal of this review is to provide a comprehensive catalog of these databases, as well as to describe the data and tools that they make available. A Directory of Databases for Plant Cell Wall-Related Enzymes (plantcellwalls.ucdavis.edu) was also developed to provide links to all the databases reviewed in this paper and relevant publications.