Hi aruna,

Please refer below article

Maintain DIV scroll position for Scrollable GridView using jQuery inside ASP.Net AJAX UpdatePanel

you need to just change your plugin in above article the scrollable plugin is updated so it will slove your issue.

and created a sample which full fill your requirement

HTML

<asp:ScriptManager runat="server" />
<asp:UpdatePanel ID="updatePanel" runat="server">
    <ContentTemplate>
        <asp:GridView ID="GridView1" AutoGenerateColumns="false" runat="server" AutoGenerateSelectButton="true"
            OnSelectedIndexChanged="GridView1_SelectedIndexChanged">
            <Columns>
                <asp:TemplateField HeaderText="OrderID">
                    <ItemTemplate>
                        <asp:Label ID="lblOrderID" Text='<%#Eval("OrderID") %>' runat="server" />
                    </ItemTemplate>
                </asp:TemplateField>
                <asp:TemplateField HeaderText="CustomerID">
                    <ItemTemplate>
                        <asp:Label ID="lblCustomerID" Text='<%#Eval("CustomerID") %>' runat="server" />
                    </ItemTemplate>
                </asp:TemplateField>
            </Columns>
        </asp:GridView>
    </ContentTemplate>
</asp:UpdatePanel>
<div>
    <script src="Scripts/ScrollableGridPlugin_ASP.NetAJAX_3.0.js" type="text/javascript"></script>
    <script type="text/javascript">
        var position = 0;
        $(document).ready(function () {
            $('#<%=GridView1.ClientID %>').Scrollable({
                ScrollHeight: 300,
                IsInUpdatePanel: true
            });
        });
    </script>
</div>

C#

protected void Page_Load(object sender, EventArgs e)
{
    if (!IsPostBack)
    {
        string constr = ConfigurationManager.ConnectionStrings["ConString"].ConnectionString;
        SqlConnection con = new SqlConnection(constr);
        SqlCommand cmd = new SqlCommand("SELECT OrderID,CustomerID FROM Orders", con);
        SqlDataAdapter sda = new SqlDataAdapter(cmd);
        DataTable dt = new DataTable();
        sda.Fill(dt);
        GridView1.DataSource = dt;
        GridView1.DataBind();
    }
}

protected void GridView1_SelectedIndexChanged(object sender, EventArgs e)
{
    int selectedIndex = GridView1.SelectedIndex;
    Label lblOrderID = GridView1.Rows[selectedIndex].FindControl("lblOrderID") as Label;
    lblOrderID.Text = "Changed OrderID";

}

ScreenShot

Hope this works for you.