A列の最終行の位置を取得
Cells(Rows.Count, “A”).End(xlUp).Row
A列が空欄ならB列に「空欄」と記入
Sub 空欄探し()
Dim i As Integer
For i = 2 To Cells(Rows.Count, "A").End(xlUp).Row 'Aの最終行
If Cells(i, 1) = "" Then
Cells(i, 2) = "空欄"
Else
Cells(i, 2) = "文字あり"
End If
Next
End Sub