خاصية Count

MessageDlg(inttostr(Workbook.Sheets[1].Hyperlinks.Count) + ' hyperlinks on Worksheet one.',
           mtInformation, [mbOk], 0);

MessageDlg(inttostr(Workbook.Sheets[1].Range['A1','D10'].Hyperlinks.Count) + ' hyperlinks on A1:D10.',
           mtInformation, [mbOk], 0);