What age should a child be disciplined? I personally believe a child should be disciplined as soon as they can understand you so anywhere from age one and up. Yes I know some people might say that is just plain Crazzzy, but just hear me out for a second. I don’t believe a child needs to be talking for them to understand you, because children understand words like “No, stop, or don’t go back there and etc…” I have a one year old and believe me when I say that she doesn’t like the words “stop, no, or don’t go back there. Whenever I tell her those words she gives me some funny facial expression like I heard you but I am still going to do it no matter how many times I say it. After telling her numerous times and she fails to listen then I let her know that she will be going into timeout since she kept doing whatever it is that I am stopping her from. So timeout is a form of discipline for me.