Background: Participation in clinical trials can be useful for the health of a person, in who it is conducted, but it does not have to be - it can even be harmful. Therefore, primary motive to accept such risk is humanity and human wish to contribute to the progress of medicine, this is expressed by personal consent. The consent, however, can be an expression of personal humanity, and for this, it is not logical that someone can give consent on behalf of someone else, as it is done by a legally authorized representative on behalf of a minor. Therefore, authors raise 3 questions: What are the reasons to consider representative's consent acceptable? How should a model of regulations look like in order to pro-vide the most complete possible protection to a minor? Is actual regulation of minors' position within international and Serbian law, analyzed here by authors for their specific solutions, acceptable? Representative's consent is acceptable only for therapeutic research, because these can bring benefits to everyone's health, including a minor in which those are conducted – this is an acceptable (secondary) motive of participation in the research. Expression of humanity on other's behalf, typical for non-therapeutic research, is not acceptable, this makes ban of minors' participation in non-therapeutic research more appropriate regulation model. International regulations are not in accordance to results presented in the paper for allowing participation of minors both in therapeutic and non-therapeutic research. Serbian regulation is closer to the most acceptable regulation model.