The main objective of this project is the study of the addition of chitosan in the polymeric blend of PVP/PVAL to get a biocompatible hydrogel that can be used as a system of controlled release of drugs. The polymeric blend usage is a recent development that expanded the applications of the polymers, due to the improvement of the properties of a single polymer even if they appear to be conflicting. PVP and PVAL were chosen because they present the main required characteristics to the formation of a hydrogel, such as water absorption and crosslinked formation. The flexibility of the PVP was added with the mechanical resistance of the PVAL. The chitosan, biological active polymer molecules, addition is to increment the interaction between the hydrogel and the organism. With the concentrations of PVP and PVAL defined, solutions with different levels of chitosan were made to check which presented better properties.