Mankind will decide at liberty the fate of his property, therefore the inheritee will be dispose of his property. But the free disposition of inheritance by the inheritee will be against to the fixed of relation’s interest in some case. So the restriction of the free principle of inheritee’s intention is required. It is the Reserve System to take charge of such function. The Reserve System is the inheritance system which is established in order to a fixed successor and the inheritee who must reserve a division of successor’s legal portion of an inheritance. Accordingly the Reserve is a fixed property which has leave behind for a the legal heir, when a inheritee disposes of his property by his donation or legacy. Our country did not adopted the Reserve System in the early Civil Code. But It is adopted at 1977 through a partial amendment of the Civil Law Act. the Reserve System in the Civil Law could protect successor who is excluded by the intention of inheritee and also it is a compromise between Will Succession System and Legal Succession System. This thesis dealt with explanation about the History of Reserve as well as legal merit on the Reserve system. On this basis, I tried to mention the distinction of our Reserve System as follows that our present Reserve System in the Civil law seems largely on the basis of Portion of Obligation in Roman Law. And a Reserve is the part of property reverted to each rightful person for a reserve, which is certain part of one’s own legal inheritance. Consequently as a rightful person for a reserve should be a successor and his reserve should be protected by his legal inheritance inseparably. The claim of restoration for a Reserve should be a right of Claim. In conclusion the Reserve is the Merit because in one side the disposal of testament principle of his Intention that he will decide at liberty the fate of the property after his death, in another side Legal Succession System is adopted as Succession of property to the fixed near relation is resonable.