The concept of ownership in condominium in France is defined by the Article 1 of the Law of 10 July 1965 states: "This Act governs any building or group of buildings whose ownership is divided among several people, composed each one by a private part and a part of common areas. ".The Lot of condominium is as a legal relationship established between perpetual vocation parts of the building to allow the distribution of its property. The condominium lot is the result of an individual appropriation with a collective process and into the wider concept of private property.Private property was designed by the French Revolution as a natural and inalienable human right, just as freedom. It is an inviolable and sacred right which no one can be private.The analys however highlights one hand great complexity on the scope of rights forming the components of the condominium lot but also its materiality. Difficulty identifying the physical reality of size lot suggests the distortion that may exist between the reality of this form of property and what the owner thinks .This Illusion present a real legal insécurity for the owner who does not measure extent of their rights and duties with respect to the nature of his property.