Dim classeur1 As Workbook Dim classeur2 As Workbook Dim cellule1 As Range Dim cellule2 As Range Set classeur1 = ActiveWorkbook Set classeur2 = Workbooks.Open("D:\Data\f2.xls") Set cellule1 = classeur1.Worksheets("Feuil1").Range("A1") Set cellule1 = classeur2.Worksheets("Feuil1").Range("A1") cellule1.Value = cellule1.Value + cellule2.Value