Drug delivery is the process or method of administering a pharmaceutical compound to attain a therapeutic effect in humans or animals. For the treatment of human diseases through nasal and pulmonary routes of drug delivery are ahead increasing importance in the field. These routes provide capable alternatives to parenteral drug delivery process and particularly for protein and peptide therapeutics. For this purpose, several drug delivery systems have been formulated and are being investigated for nasal and pulmonary delivery of the drug. These include proliposomes, liposomes, microspheres, prodrugs, gels, cyclodextrins, among others. Biodegradable polymers which are composed of Nanoparticles shows assurance in fulfilling the perfect requirements placed on these delivery systems, such as capability to be transferred into an aerosol, stability during aerosolization against forces generated, biocompatibility, targeting of specific cell or sites populations in the lung, release of the drug in a predetermined manner, and degradation within an acceptable period of time.