{ With OLE Automation }
 uses
  ComObj;
 function RefToCell(ARow, ACol: Integer): string;
 begin
  Result := Chr(Ord('A') + ACol - 1) + IntToStr(ARow);
 end;
 function SaveAsExcelFile(AGrid: TStringGrid; ASheetName, AFileName: string): Boolean;
 const
  xlWBATWorksheet = -4167;
 var
  Row, Col: Integer;
  GridPrevFile: string;
  XLApp, Sheet, Data: OLEVariant;
  i, j: Integer;
 begin
  // Prepare Data
 Data := VarArrayCreate([1, AGrid.RowCount, 1, AGrid.ColCount], varVariant);
  for i := 0 to AGrid.ColCount - 1 do
  for j := 0 to AGrid.RowCount - 1 do
  Data[j + 1, i + 1] := AGrid.Cells[i, j];
  // Create Excel-OLE Object
 Result := False;
  XLApp := CreateOleObject('Excel.Application');
  try
  // Hide Excel
  XLApp.Visible := False;
  // Add new Workbook
  XLApp.Workbooks.Add(xlWBatWorkSheet);
  Sheet := XLApp.Workbooks[1].WorkSheets[1];
  Sheet.Name := ASheetName;
  // Fill up the sheet
  Sheet.Range[RefToCell(1, 1), RefToCell(AGrid.RowCount,
  AGrid.ColCount)].Value := Data;
  // Save Excel Worksheet
  try
  XLApp.Workbooks[1].SaveAs(AFileName);
  Result := True;
  except
  // Error ?
  end;
  finally
  // Quit Excel
  if not VarIsEmpty(XLApp) then
  begin
  XLApp.DisplayAlerts := False;
  XLApp.Quit;
  XLAPP := Unassigned;
  Sheet := Unassigned;
  end;
  end;
 end;
 // Example:
procedure TForm1.Button1Click(Sender: TObject);
 begin
  if SaveAsExcelFile(stringGrid1, 'My Stringgrid Data', 'c:\MyExcelFile.xls') then
  ShowMessage('StringGrid saved!');
 end;

{ Without OLE }
 procedure XlsWriteCellLabel(XlsStream: TStream; const ACol, ARow: Word;
  const AValue: string);
 var
  L: Word;
 const
  {$J+}
  CXlsLabel: array[0..5] of Word = ($204, 0, 0, 0, 0, 0);
  {$J-}
 begin
  L := Length(AValue);
  CXlsLabel[1] := 8 + L;
  CXlsLabel[2] := ARow;
  CXlsLabel[3] := ACol;
  CXlsLabel[5] := L;
  XlsStream.WriteBuffer(CXlsLabel, SizeOf(CXlsLabel));
  XlsStream.WriteBuffer(Pointer(AValue)^, L);
 end;

 function SaveAsExcelFile(AGrid: TStringGrid; AFileName: string): Boolean;
 const
  {$J+} CXlsBof: array[0..5] of Word = ($809, 8, 00, $10, 0, 0); {$J-}
  CXlsEof: array[0..1] of Word = ($0A, 00);
 var
  FStream: TFileStream;
  I, J: Integer;
 begin
  Result := False;
  FStream := TFileStream.Create(PChar(AFileName), fmCreate or fmOpenWrite);
  try
  CXlsBof[4] := 0;
  FStream.WriteBuffer(CXlsBof, SizeOf(CXlsBof));
  for i := 0 to AGrid.ColCount - 1 do
  for j := 0 to AGrid.RowCount - 1 do
  XlsWriteCellLabel(FStream, I, J, AGrid.cells[i, j]);
  FStream.WriteBuffer(CXlsEof, SizeOf(CXlsEof));
  Result := True;
  finally
  FStream.Free;
  end;
 end;
 // Example:
procedure TForm1.Button2Click(Sender: TObject);
 begin
  if SaveAsExcelFile(StringGrid1, 'c:\MyExcelFile.xls') then
  ShowMessage('StringGrid saved!');
 end;

{ Code by Reinhard Schatzl }
 uses
  ComObj;
 // Hilfsfunktion fur StringGridToExcelSheet
// Helper function for StringGridToExcelSheet
function RefToCell(RowID, ColID: Integer): string;
 var
  ACount, APos: Integer;
 begin
  ACount := ColID div 26;
  APos := ColID mod 26;
  if APos = 0 then
  begin
  ACount := ACount - 1;
  APos := 26;
  end;
  if ACount = 0 then
  Result := Chr(Ord('A') + ColID - 1) + IntToStr(RowID);
  if ACount = 1 then
  Result := 'A' + Chr(Ord('A') + APos - 1) + IntToStr(RowID);
  if ACount > 1 then
  Result := Chr(Ord('A') + ACount - 1) + Chr(Ord('A') + APos - 1) + IntToStr(RowID);
 end;
 // StringGrid Inhalt in Excel exportieren
// Export StringGrid contents to Excel
function StringGridToExcelSheet(Grid: TStringGrid; SheetName, FileName: string;
  ShowExcel: Boolean): Boolean;
 const
  xlWBATWorksheet = -4167;
 var
  SheetCount, SheetColCount, SheetRowCount, BookCount: Integer;
  XLApp, Sheet, Data: OLEVariant;
  I, J, N, M: Integer;
  SaveFileName: string;
 begin
  //notwendige Sheetanzahl feststellen
 SheetCount := (Grid.ColCount div 256) + 1;
  if Grid.ColCount mod 256 = 0 then
  SheetCount := SheetCount - 1;
  //notwendige Bookanzahl feststellen
 BookCount := (Grid.RowCount div 65536) + 1;
  if Grid.RowCount mod 65536 = 0 then
  BookCount := BookCount - 1;
  //Create Excel-OLE Object
 Result := False;
  XLApp := CreateOleObject('Excel.Application');
  try
  //Excelsheet anzeigen
  if ShowExcel = False then
  XLApp.Visible := False
  else
  XLApp.Visible := True;
  //Workbook hinzufugen
  for M := 1 to BookCount do
  begin
  XLApp.Workbooks.Add(xlWBATWorksheet);
  //Sheets anlegen
  for N := 1 to SheetCount - 1 do
  begin
  XLApp.Worksheets.Add;
  end;
  end;
  //Sheet ColAnzahl feststellen
  if Grid.ColCount <= 256 then
  SheetColCount := Grid.ColCount
  else
  SheetColCount := 256;
  //Sheet RowAnzahl feststellen
  if Grid.RowCount <= 65536 then
  SheetRowCount := Grid.RowCount
  else
  SheetRowCount := 65536;
  //Sheets befullen
  for M := 1 to BookCount do
  begin
  for N := 1 to SheetCount do
  begin
  //Daten aus Grid holen
  Data := VarArrayCreate([1, Grid.RowCount, 1, SheetColCount], varVariant);
  for I := 0 to SheetColCount - 1 do
  for J := 0 to SheetRowCount - 1 do
  if ((I + 256 * (N - 1)) <= Grid.ColCount) and
  ((J + 65536 * (M - 1)) <= Grid.RowCount) then
  Data[J + 1, I + 1] := Grid.Cells[I + 256 * (N - 1), J + 65536 * (M - 1)];
  //-------------------------
  XLApp.Worksheets[N].Select;
  XLApp.Workbooks[M].Worksheets[N].Name := SheetName + IntToStr(N);
  //Zellen als String Formatieren
  XLApp.Workbooks[M].Worksheets[N].Range[RefToCell(1, 1),
  RefToCell(SheetRowCount, SheetColCount)].Select;
  XLApp.Selection.NumberFormat := '@';
  XLApp.Workbooks[M].Worksheets[N].Range['A1'].Select;
  //Daten dem Excelsheet ubergeben
  Sheet := XLApp.Workbooks[M].WorkSheets[N];
  Sheet.Range[RefToCell(1, 1), RefToCell(SheetRowCount, SheetColCount)].Value :=
  Data;
  end;
  end;
  //Save Excel Worksheet
  try
  for M := 1 to BookCount do
  begin
  SaveFileName := Copy(FileName, 1,Pos('.', FileName) - 1) + IntToStr(M) +
  Copy(FileName, Pos('.', FileName),
  Length(FileName) - Pos('.', FileName) + 1);
  XLApp.Workbooks[M].SaveAs(SaveFileName);
  end;
  Result := True;
  except
  // Error ?
  end;
  finally
  //Excel Beenden
  if (not VarIsEmpty(XLApp)) and (ShowExcel = False) then
  begin
  XLApp.DisplayAlerts := False;
  XLApp.Quit;
  XLAPP := Unassigned;
  Sheet := Unassigned;
  end;
  end;
 end;
 //Example
procedure TForm1.Button1Click(Sender: TObject);
 begin
  //StringGrid inhalt in Excel exportieren
 //Grid : stringGrid, SheetName : stringgrid Print, Pfad : c:\Test\ExcelFile.xls, Excelsheet anzeigen
 StringGridToExcelSheet(StringGrid, 'Stringgrid Print', 'c:\Test\ExcelFile.xls', True);
 end;