Epithelial cell lines are commonly accepted model system to determine intestinal permeability and transepithelial transport. The application of Caco-2 human epithelial cell culture can be used to study bioavailability of drug and food compounds. This culture grows on porous membranes and forms a monolayer of well differentiated cells joined by intracellular tight junctions. This system provides selective barrier to study passive and active transport of different molecules. The Caco-2 cells posses some enzymes and transport systems similar to intestinal epithelium in vivo, however, these proteins are expressed to a lesser extent compared to normal enterocytes. In this paper, the advantages and limitations of Caco-2 model are discussed.