This thesis considered the improvement plan carefully for safety of a real estate transaction on register of real property, system of authentication certificate of one's seal, substantial right to the investigation of greffier, and so on. And the rules and theorization that protect third party that trusts incorrect registration were reviewed under current law that public confidence on register of real property is not admitted. The research result for safety of a real estate transaction on register of real property and prevention of incorrect registration is as in the following. The acquisition, loss of, or any alteration in, a real right by a juristic act over an immovable takes effect upon its registration. The acquisition of real rights over immovables through inheritance, expropriation, judgment, auction and others stipulated in provisions of law shall not require registration. Provided, that the immovable shall not be disposed of unless it has been registered. A sale shall become effective when one of the parties agrees to transfer a property right to the other party and the other party agrees to pay the purchase-price to the former. And One of the parties to a bilateral contract may refuse performance of his own obligation until the other party tenders performance of his obligation. Provided, that this shall not apply where the obligation of the other party is not due. Therefore, although down payment and middle payment by a real estate transaction after conclusion of a sales contract is paid, a buyer should pay balance to receive document for registration of ownership transfer. Accordingly, a buyer feels uneasy for the period. The prior disclosure system should be introduced to solve slippery situation of a buyer, secure safety of a real estate transaction and improve trust of register of real property. The register of real property is recorded by application for registration by Registration of Real Estate Act. Unless prescribed otherwise by any Act, registration shall be applied jointly by a person entitled to file for a registration and a person obliged to file for a registration. The Principle of Application of this act is as in the following. Article 22 (1) Registration shall be made by application of an interested party or on the entrustment of a public office. (2) Unless otherwise prescribed by any Act to the contrary, provisions concerning registration by application shall apply mutatis mutandis to the procedures for registration on entrustment. (3) Anyone who intends to file for a registration shall pay fees, as prescribed by the Supreme Court Regulations. And Unless prescribed otherwise by any Act, registration shall be applied jointly by a person entitled to file for a registration and a person obliged to file for a registration. Especially, this act is to prescribe matters concerning the registration of real estate. The registration of real estate should be recorded by force within a reasonable compass to achieve purpose of system on the registration of real estate. Registration shall be applied by any of the following two methods. 1. An applicant or his/her agent goes to a registry and submits documents stating application information and accompanying information. Provided, that when such agent is an attorney (including a law firm, a law firm with limited liability, and a judicial association) or a certified judicial scrivener (including a corporation of certified judicial scriveners and a corporation of certified judicial scriveners with limited liability), he/she may require a clerk prescribed by the Supreme Court Regulations to go a registry and submit such documents. 2. Application information and accompanying information are sent via a computerized data processing system, as prescribed by the Supreme Court Regulations (limited to the type of registration designated by the Minister of Supreme Court Administration). More than 95 percent of the register of real property were recorded by an attorney or a certified judicial scrivener. Therefore, theses agent neeed to identify whether the parties want to record the register of real property to prevent incorrect registration. And an attorney or a certified judicial scrivener should submit copy of resident registration of the parties to prevent illegal issuance of authentication certificate of one's seal that counterfeits identification. Meanwhile, the notice of application on authentication certificate of one's seal by an attorney or a certified judicial scrivener should be reported to prevent illegal forge of authentication certificate of one's seal. Therefore, the real a rightful person that is deprived right by admitting public confidence on register of real property should receive indemnity for a damage done. Ultimately, the study should be reviewed by legislation in order to admit certain condition for safety of a real estate transaction.