Mucoadhesive gels were prepared for the treatment of oral sub mucous fibrosis, which provide effect for extended periods of time. Stress was given for improvised local action of the drug with the addition of mucoadhesive polymer in the formulation. Curcumin was taken as a model drug as it exhibits profound antitumeric & antimutogenic activity. The semisolid preparations comprised of stabilizer like sodium metabisulphite, muco retention / mucoadhesive polymers like HEC, NaCMC and equal mixture of HEC & NaCMC, and were subjected for various pysicochemical parameters like pH, spreadability, drug content uniformity, extrudability, viscosity & I.R. studies. In-vitro drug release studies were carried out in phosphate buffer (6.4 pH). Stability studies were also done at room temperature for a period of eight weeks. Among three formulations (formulation code F1 containing equal mixture of NaCMC & HEC as base, formulation code F2 containing NaCMC as base and formulation code F3 containing HEC as base), the formulation containing equal mixture of NaCMC & HEC as base showed good in-vitro release and good adhesion to oral mucosae. IR studies showed that there was no drug-excipient interaction. The in-vivo studies were carried out in two phases using 18 mice with the permission of ethical committee under the supervision and help of staff, Department of Pathology, M.R. Medical College, Gulbarga. In first phase oral sub mucous fibrosis was induced in mice using marketed Gutkha preparation and formulating into a mucoadhesive gel form and applying to mice oral mucosa with the help of cotton bud for a period of 6 months. In second phase, treatment was carried out following the above method using curcumin formulation. The tissue samples collected for 1, 3 & 6 months induction period & 1, 3 & 6 months of treatment period on 6 months oral sub mucous fibrosis induced mice. Histopathological observations reported that there was considerable induction of oral sub mucous fibrosis and excellent treatment results on curcumin usage. The results of the present study of mucoadhesive semi-solid drug design for the treatment of oral sub mucous fibrosis will be useful for drug industry for the benifit of patients suffering from oral sub mucous fibrosis.