From the pioneering work of J. Piaget "The moral judgment of the child" we have reviewed the contributions to this study of childrens' conception of stealing . Using a story about a minor theft, we examined how kindergarten children answer questions about the right and wrong of stealing and now they justified their answers. In addition we examined childrens' perception of the existence, contingence and relativity of rules. We examined 80 children from a public and a private school, each divided in two groups. The results have shown that children have a notion of stealing as a wrong act and to justify these answers they show five patterns of justifications, as well as judgment of intentionality. Results were discussed in terms of Piaget's moral development theory.