In this paper, we have clarified the necessity and motivation about legal act of discerning minor. After this introduction, we have classified related subjects into two topics and here we have investigated each one of them. In first topics of concepts and definitions, discerning minor and legal acts have been investigated. For second topic, we have selected legal acts of discerning minor and have investigated legal acts based on discerning minor from correctness and veracity, invalidity and impermeability, Islamic religious laws points of views and also we have investigated views of some countries in this respect. In second parts, we presented doing legal acts of discerning minor as representation and after that we have talked with natural guardian, trustees, and executor of will in position of signing a contract and doing legal act and restriction of mentioned representations.