You can try like bellow,
Protected Sub Load_GridView(ByVal sender As Object, ByVal e As System.EventArgs) Handles GridView1.Load
Try
GridView1.Columns.Clear()
Dim colf As CommandField = New CommandField
colf.EditText = "Edit"
GridView1.Columns.Insert(0, colf)
Catch ex As Exception
End Try
End Sub