Leasehold is a kind of obligatory right. There are two reasons for enhancing the legal protection of the lessee of real estate. One is that most of the lessees of structural improvement and agricultural land are poor in economics, so it is necessary to protect their right to exist. The other one is to ensure the investment of the land investor, enhance their desire in investing and develop the value of lands to promote the development of economics. Therefore, it is necessary to enhance the legal status of lessees of real estate to make the leasehold turn to have the character of real right. The most important standard to judge whether the leasehold turns to have the character of real right is the effect against the transferee. It is also called the principle of “Kauf bricht nicht Miete”. The civil law of Germany provides that the principle of “Kauf bricht nicht Miete” applies to the lease of real estate. The civil law of Japan adopts the principle of “Kauf bricht Miete”, but after the war between Japan and Russia, the government of Japan also adopts the principle of “Kauf bricht nicht Miete” through special law under the situation of the lease of real estate. Compared with foreign legislation, the revision of our civil law adds the article which provides that the principle of “Kauf bricht micht Miete” would not apply to a lease of an immovable which is without notarization and the lease term is beyond five years or without a time-limit. This article is not only inequitable in legislative policy, but also against the rule of capital movement and interferes with the use of land and the development of economics. Therefore, this article should be deliberated more carefully.