Dear All, The simplest way of create nested datalist with parent child table relation is given below: protected void loadData() { //Note: For Define your connection string i am not writing it because it is in my web.config and i load it through my internal class DataSet ds = new DataSet(); // my private class that contains sql execute funtions, I pass the SQL parameters and Values through array UDF myudf = new UDF(); string spName = "bvs_payInvoice"; string[] field = new string[5]; string[] fieldValue = new string[field.Length]; field[0] = "@startDate"; field[1] = "@endDate"; field[2] = "@searchType"; field[3] = "@keyWord"; field[4] = "@status"; fieldValue[0] = startDate; fieldValue[1] = endDate;