DataGridView1.Rows.Clear()
      
With DataGridView1

        .Rows.Add("1", "AAA")
        .Rows.Add("2", "BBB")
        .Rows.Add("3", "CCC")
        .Rows.Add("4", "DDD")
        .Rows.Add("5", "EEE")

End With

==== หรือ ====

Dim dt As New DataTable
DataGridView1.DataSource = dt