Polymers are becoming increasingly important in the field of drug delivery. The pharmaceutical applications of polymers range from their use as binders in tablets to viscosity and flow controlling agents in liquids, suspensions and emulsions. Use of polymer is now extended to controlled release and targeting drug delivery system. Polymers are obtained from natural source as well as synthesized chemically. Polymers are classified as biodegradable and nonbiodegradable. Biodegradable polymers have been widely used in biomedical applications because of their known biocompatibility and biodegradability. The present review gives an overview of the different biodegradable polymers that are currently being used in the development of controlled drug delivery system.