As a limitation to the freedom of testamentary disposition, under the influence of the Roman legal tradition, the institute of compulsory inheritance law was established. Its role today is the same as it was then, namely that it represents the rules governing the circle of persons to whom the testator is obliged to leave a certain part of the estate (against his will) for the purpose of protecting his closest relatives. Today, when there has been a change in the purpose that family units had in the past, the necessary right of inheritance limits other rights such as the right to property and autonomy of will. By applying historical, comparative, and analytical methods, the paper critically examines the arrangement of the necessary inheritance law. The aim of this paper is to show the legislator how strictly this institute is regulated in our inheritance legal system, and some of its main disadvantages are controversy and inflexibility, so it is necessary to introduce certain changes. The paper summarizes the most necessary changes, which primarily concern the transition to mandatory legal nature (with certain exceptions), narrowing the circle of potential necessary heirs, but changes in the size of the necessary part and reducing the deadlines by which the necessary heir can claim his right would also be desirable. Here, as an example, the legislator was offered certain solutions modeled on other legal arrangements. With every change, even the smallest one, the legislator would contribute not only to increasing the flexibility of this institute but also to greater respect for the testator's last will.