The characterization peaks of Imatinib mesylate were found in formulation undisturbed indicates the compatibility of the drug used with the excipients of the formulation.The monograph of Imatinib mesylate has melting point range of 214-224°C. The sample of Imatinib mesylate obtained from Dr. MACS Bio Pharma Pvt Ltd, Hyderabad. Indicating the purity of the drug sample. Clarity of all the formulations was found to be satisfactory. The pH of all formulations was found to be satisfactory and lies in the range 7.03±0.1 to 7.54±0.2. The drug content uniformity data has shown that all the formulations were found to be uniform in drug content in the range of 95.05-99.25%. Gelation study was performed to explain gelling capacity. Gelling capacity of all formulations were designated as + (gel formation takes after few minutes and disperse rapidly), ++(immediate gel formation, remains un-dispersed for few hours) and +++ (immediate gel formation, the gel was remains for extend time). The results of rheological study of prepared in situ gel confirms as the viscosity decreases with increase in angular velocity. Results indicated that all formulations are having an optimum viscosity and all formulations were pourable at normal conditions. The drug release data obtained for all the formulations were shown in fig 4.5. The cumulative percent drugrelease of formulation was 99.25±3.5 for formulation 1, For formulations F2 to F6 the values 98.25±2.5, 95.05±2.5, 96.32±1.3, 95.27±0.2 and 98.24±1.5respectively till 12th hour. From the result of drug content, gelation pH, drug content, and drug release studies for all formulation, F6 formulation was selected as best formulation which has shown highest drug release till 12thhour. Hence F6formulation was chosen for stability studies.