I got the answer as
I place a hidden field as
<input type="hidden" id="hdnScrollTop" runat="server" value="0" />
and in div add a function
<div id="dvScroll" onscroll="$get('ctl00_ContentPlaceHolder1_hdnScrollTop').value = this.scrollTop;">
The javascrip is
var prm = Sys.WebForms.PageRequestManager.getInstance();
prm.add_pageLoaded(pageLoaded);
prm.add_beginRequest(beginRequest);
var postbackElement;
function beginRequest(sender, args) {
postbackElement = args.get_postBackElement();
}
function pageLoaded(sender, args) {
var updatedPanels = args.get_panelsUpdated();
if (typeof (postbackElement) == "undefined") {
return;
}
if (postbackElement.id.indexOf('gridViewList') > -1) {
try {
$get("divScroll").scrollTop = $get("ctl00_ContentPlaceHolder1__hdnScrollTop").value;
}
catch (Err) {
}
}}
This solved my problem.