1.You describe someone as childlike when they seem like a child in their character, appearance, or behaviour. example: He has a childlike ignorance. 2. If you describe someone, especially an adult, as childish, you disapprove of them because they behave in an immature way example:Her remarks are childishly simplistic childlike is more of positive, whereas childish sounds more negative.

"Childlike" is used to describe a person. "Childish" is used to describe a behavior.