This article aims at describing the obseroance of wasiat wajibah (compulsory bequeathment) in the Islamic court of Banten, analyzing the provision of the substitute heir and adopted children in the Compilation of Islamic Law (KHI). In addition, the ideal laws to manage the innheritance rules in Indonesia. This article is library research by using doctrinal approach and using case study and survey methods. The data was, then, analyzed by using analytical descriptive and analytical correlative methods. The result showed that the observance of wasiat wajibah in the Islamic court of Banten employed by judges is by using the Mawali Hazairin’s Doctrine. The criteria of the adoption of substitute heir and adopted children in the KHI is the attempts of Ulama and many judgees junst in giving legal justice and certainty to the society.
Key Words: Islamic Inheritance Law, Compilation of Islamic Law, Islamic court of Banten
