The title of this thesis is “Legal Issues in connection with the Civil Responsibility of Legal Owner in the Acquisitive Prescription system of the Ownership of Real Property”. It would be difficult at the present moment to predict exactly what problems may arise in the future. However, there should be efforts to find solutions for problems related to regulation of public order so that the risk of causing unreasonable consequences can be minimized. Civil law article 245(Period for Acquiring Ownership of Immovables by Possession) is prescribing (1) A person who has for twenty years peaceably and openly held possession of an immovable with an intention to own it, shall acquire the ownership by making registration thereof. (2) A person, who has made registration as the owner of an immovable and has for ten years peaceably and openly held possession of an immovable with the intent to own it, shall acquire the ownership of such immovable if his possession is in good faith and without negligence. Our Civil Law takes "Erklrungstheorie(Formalism)" and equally admits the prescription by registration and the occupancy prescription alike. Unlike other countries' Civil Law that takes "Willenstheorie" and admits the occupancy prescription, it also requires registration as the qualification of the occupancy prescription. Because of this reason, many problems are caused. I explained about the main contents of acquisitive prescription system and dealt with the important contents of the acquisitive prescription system of real property and suggested especially the problems and improvements in connection with the civil responsibility of legal owner in the acquisitive prescription of real property.