The inheritance law adhered to indigenous Batak Toba people is patrilineal system, where the right to inherit their parents' inheritance is a boy. While girls do not get inheritance except by way of grants. The position of adat batak adat girls basically do not get the right of inheritance from their parents. But with the development of the current era, the patrilineal system adhered to the inheritance of adat batak is not always adhered to by the indigenous people of Batak. It can be seen from some traditional leaders interviewed in Pematangsiantar city. It provides information that the daughter who has received the inheritance from her parents, where the division of the inheritance is the same as the son. Some changes that occur in the inheritance of adat batak, among others, changes in terms of education, migration / migration, economic, religious and social. The method used in this research is empirical juridical and analytical descriptive method that describes, describes and reveals how the actual customary law of batak that has developed today. From the result of this research we can know that, because of the system‟s development nowadays the law of inheritance according to the Batak‟s tradition has determined that there is the same right between men and woman in the matter of inheritance.