It is within bounds to say that today transparency is becoming the conversation topic of all the fields. The real estate market is not exception. Many countries realized the importance of transparency in the real estate market and have made efforts to improve transparency. So, transparency has became greater for recent years. The extent of transparency is remaining considerably stable. The following two things are prerequisites for the improvement of transparency in the real estate market. One is to define the concept transparency. The other is to establish standards and elements for judging transparency. We cannot examine the improvement of transparency and its plan as well as the judgement of transparency until we establish the definition of this concept. This research has a significance of putting questions having a critical mind about the above things. This research aimed to examine the concept and criteria of transparency in the real estate market and suggest the task and plan for improving the real estate market in Korea, based on Jones Lang LaSalle's GRETI (global real estate transparency index). The price reporting system in real estate transaction and the public notification system of real estate register can be judged to have achieved an epoch-making improvement of transparency, on the grounds of transparency in real estate transaction and a yardstick of judgment of transparency (i.e. the basic structure of the real estate market). Non-activation of real estate securitization, in particular REITs (real estate investment trusts), is a factor of not enabling Korea's real estate market to obtain a good grade in the evaluation of transparency. The real estate market in Korea lacks information of commercial real estate (e.g. monthly rent in shopping districts, etc.). Further, all sorts of statistical data about general real estate are not satisfactory.