The sports environment can be considered as a context characterized by interactions typical of social groups, where children have the chance to learn good values. Positive and negative behaviours in sports, also called prosocial and antisocial behaviours, have been studied according to a moral perspective, as has doping behaviour, taking into consideration the concept of moral disengagement. Moral disengagement in children has been associated with maladaptive behaviours later in life, even though it should disappear with growth. Concerning the sports environment, previous reviews on the topic have extensively illustrated the role of moral variables in sport and their relation to antisocial behaviour and doping, positing some research questions that should be investigated in the future. Starting from these questions, the current narrative review aims to update literature about the effects of moral disengagement on youth athletes. Therefore, new studies about the predictors of moral disengagement are introduced, followed by contributions concerning the relationship between moral disengagement and doping and between moral disengagement and antisocial behaviour. Finally, the review summarizes which research questions have been solved in the last decade and which should be researched further on.