Thankyou Frank.i got the idea. Here is the working code.
Option Explicit
Private Sub CommandButton1_Click()
Dim directory As String, fileName As String, sheet As Worksheet, total As Integer
Dim fd As Office.FileDialog
Set fd = Application.FileDialog(msoFileDialogFilePicker)
With fd
.AllowMultiSelect = False
.Title = "Please select the file."
.Filters.Clear
.Filters.Add "Excel 2003", "*.xls?"
If .Show = True Then
fileName = Dir(.SelectedItems(1))
End If
End With
Application.ScreenUpdating = False
Application.DisplayAlerts = False
Workbooks.Open (fileName)
For Each sheet In Workbooks(fileName).Worksheets
total = Workbooks("import-sheets.xlsm").Worksheets.Count
Workbooks(fileName).Worksheets(sheet.Name).Copy _
after:=Workbooks("import-sheets.xlsm").Worksheets(total)
Next sheet
Workbooks(fileName).Close
Application.ScreenUpdating = True
Application.DisplayAlerts = True
End Sub