Hi Vijay Debugging java script in asp.net mostly depents on client side utilities. first it depends which browser and asp.net technology(1.1, 2.0, 3.5 or 4.0) you are using. in asp.net 3.5 you can get new features like Trace using ajax extension and also various browsers supports javascript debugging such as in Mozilla you can use firebug, in Safari there is developer's tag and internet explorer better works with ajax trace. just go through this utilities and ajax extension (if using framework greater than 2.0). this will definately work :) Thanks Ankur Sharma