YOu need to be a little more specific in your question for starters. Is the would healing, or is there drainage? Have you been given directions to follow?
If you had major surgery then I would contact your doctor and see what he says. If it is a minor wound, then don't itch it. The itching is a sign that the wound is healing- and that's good. Try putting a warm compress on it and see if that doesn't take the itch away. Or you can itch gently on either side of the scar but do not itch across the scar itself. YOu don't want to break the site that is healing.