Chitosan based microspheres containing were prepared by the emulsion cross linking method for nasal delivery of zolmitriptan. Nasal microspheres offer significant advantages over other type of drug delivery system. It modulates absorption characteristics of the drug by enhancing drug residence time in the nasal cavity and subsequently may increase bioavailability profile of administered drug. For the present study, Chitosan was selected as a mucoadhesive polymer. The microspheres were evaluated with respect to the particle size, production yield, encapsulation efficiency, shape and surface properties, drug and polymer interaction, mucoadhesive property, in vitro drug release. To optimize the microsphere formulation, 23factorial design was employed for investigating the effect of three factors, polymer concentration (chitosan), emulsifier concentration (Span 80) and cross-linking agent (gluteraldehyde) on response variable, which are encapsulation efficiency, in vitro drug release.