请教，在VBA 窗体控件Label上如何显示一个倒计时？比如30分钟的倒计时。谢谢。

是窗体上的Label1控件？还是表格上的Label1控件？

下面的是表格上的Label1控件，如果你设计了窗体，把引用改一下就可以了。

双击标签开始10秒倒计时，再双击停止倒计时。

Dim tgtTm As Date, rmTm As Date, IsRun As Boolean
Const Intv = #12:00:01 AM#
Private Sub Label1_DblClick(ByVal Cancel As MSForms.ReturnBoolean)
If IsRun Then
Application.OnTime Now() + Intv, "'Sheet1.MyTimer'", , False
IsRun = False
Else
rmTm = #12:00:10 AM#
tgtTm = Now() + rmTm
Label1.Caption = Format(rmTm, "hh:mm:ss")
Application.OnTime Now() + #12:00:01 AM#, "'Sheet1.MyTimer'"
IsRun = True
End If
End Sub
'-----计时器-----
Private Sub MyTimer()
rmTm = tgtTm - Now()
If rmTm > 0 Then
Application.OnTime Now + Intv, "'Sheet1.MyTimer'"
IsRun = True
Else
rmTm = 0
IsRun = False
End If
Label1.Caption = Format(rmTm, "hh:mm:ss")
End Sub

Private Sub CommandButton1_Click()
st = Now()
t = CDate("00:30:00")
Label1.Caption = t
Do
DoEvents
If DateDiff("s", st, Now()) = 1 Then
st = Now()
t = DateAdd("s", -1, t)
If Minute(t) = 0 And Second(t) = 0 Then Exit Do
Label1.Caption = t
End If
Loop
End Sub