Me.ListBox1.AddItem

 If .Rows(i).Hidden = False Then Me.ListBox1.AddItem .Range("K" & i)

Private Sub UserForm_Initialize()With Sheets("Feuil1")
    For i = 2 To .Range("A65536").End(xlUp).Row + 2
        If Rows(i).Hidden = False Then Me.ListBox1.AddItem .Range("K" & i)
    Next i
End With
End Sub

Private Sub UserForm_Initialize()
Dim dl As Integer
Dim cel As Range


With Sheets("Feuil1")
    dl = .Cells(Application.Rows.Count, 1).End(xlUp).Row
    For Each cel In .Range("K2:K" & dl).SpecialCells(xlCellTypeVisible)
        Me.ListBox1.AddItem cel.Value
    Next cel
End With
End Sub