This paper presents a comparative study of the pre and post-merger financial and operating performance appraisal of merged banks. Randomly four cases of mergers occurred in the year from 2006-2010 in the Indian banking sector has been taken for the study. Camel model (camel stand for capital adequacy, asset quality, Managerial efficiency, earnings quality and liquidity) have been used to examine the pre and post-merger financial performance appraisal of acquiring banks. In order to test the degree of variation, coefficient of variation has applied. The results indicated that there is significant difference in the overall performance of merged banks during merger period hence null hypothesis is rejected.