ABSTRACT :  In the nasal cavity, nasal mucosa had a high blood perfusion rate, due to this the absorption of the drug is high as compared to another route, as well as has increased good bioavailability of drug at the systemic circulation. To improve the nasal retention time of in-situ gel with nasal mucosa we have to use bio-compatible mucoadhesive polymer. In situ gel nasal drug delivery system is the type of mucoadhesive drug delivery system. When the drug is administered through the nasal route then the first-pass metabolism gets reduced, had less enzymatic reaction occurrence, and prevents gastrointestinal tract Ulceration. Drug release kinetic can be controlled by the Gelation strength of the formulation and viscosity of the in-situ gel formulation, so in-situ gel nasal drug delivery is also called a controlled and sustained drug delivery system. In-situ gels are prepared by various types of phenomenon and techniques that depend upon the different types of polymers used in the formulation.