at first you have to select the reference named:microsoft excel 10.0 object lib and microsofr office 10.0 object lib then u may use this or some thing like this ==> string Path = @fileName; // initialize the Excel Application class Excel.ApplicationClass app = new ApplicationClass(); // create the workbook object by opening the excel file. Excel.Workbook workBook = app.Workbooks.Open(Path,0,true,5,pass1,pass2, true, Excel.XlPlatform.xlWindows,"\t",false,false,0,true,1,0); // get the active worksheet using sheet name or active sheet Excel.Worksheet workSheet = (Excel.Worksheet)workBook.ActiveSheet; // This row,column index should be changed as per your need. // i.e. which cell in the excel you are interesting to read. int row=2; while ( ((Excel.Range)workSheet.Cells[row,1]).Value2 != null ) { for(int a=1;a<=col;a++) { if(((Excel.Range)workSheet.Cells[row,a]).Value2 != null ) totSiz[row-2,a]= ((Excel.Range)workSheet.Cells[row,a]).Value2.ToString(); } row++; }