The Document of Joseon Tongsinsa is a generic term regarding Tongsinsa, diplomatic delegation dispatched to Japan 12 times with the invitation of Tokugawa shogunate from 1607 to 181 1. The Document of Joseon Tongsinsa contains the historic experiences and wisdom of Joseon and Japan that experienced disastrous wars and established and maintained peace with nothing missed. It also contains the spirit of exchange that respected each other to practice SeongsingyorinCrelationship with sincerity and trust) in the equal status. Therefore, the Document of Joseon Tongsinsa has remarkable and universal value to solve tasks of eternal peaceful coexistence and respect of other culture, which are human's common issues, as a peaceful. intellectual heritage proved by the two countries' historical experience. Documents of Joseon Tongsinsa that are registered as UNESCO Memory of the World are total 333 pieces of 111 cases, among which documents belonging to Korea are 124 pieces of 63 cases, and those belonging to Japan are 209 pieces of 48 cases. These can be broadly classified into diplomatic record, journey record and cultural exchange record. The diplomatic record is 51 pieces of 5 cases(Korea 32 pieces of 2 cases, Japan 19 pieces of 3 cases), the journey record is 136 pieces of 65 cases(Korea 67 pieces of 38 cases, Japan 69 pieces of 27 cases) , and the cultural exchange record is 146 pieces of 41 cases(Korea 25 pieces of 23 cases, Japan 121 pieces of 18 cases). Being registered as UNESCO Memory of the World basically means the materials are valuable ones that hold universal values, but at the same time , they are the ones that need special attention in preservation and improvement of accessibility. Then , what is the method to preserve the documentary heritages and to improve their accessibility according to the intention of UNESCO Memory of the World? Most urgently , the information of the records should be open to public in order to improve the accessibility of documentary heritages. The information here means the whole contents that the records contain beyond release of records. Being open to public means the contents of records should be interpreted for normal people to easily understand and be published in books or be on website. In other words, the whole contents of sahaeng-ilgi, poetry and prose, and letters along with all the poems of paintings and calligraphic works should be open to public through books or website after being interpreted. The meanings of documentary heritages are difficult to be conveyed without texts due to their characteristics. Therefore, institutions holding documentary heritages should secure budget and specialized manpower record and cultural exchange record. The diplomatic record is 51 pieces of 5 cases(Korea 32 pieces of 2 cases, Japan 19 pieces of 3 cases), the journey record is 136 pieces of 65 cases(Korea 67 pieces of 38 cases, Japan 69 pieces of 27 cases) , and the cultural exchange record is 146 pieces of 41 cases(Korea 25 pieces of 23 cases, Japan 121 pieces of 18 cases). Being registered as UNESCO Memory of the World basically means the materials are valuable ones that hold universal values, but at the same time , they are the ones that need special attention in preservation and improvement of accessibility. Then , what is the method to preserve the documentary heritages and to improve their accessibility according to the intention of UNESCO Memory of the World? Most urgently , the information of the records should be open to public in order to improve the accessibility of documentary heritages. The information here means the whole contents that the records contain beyond release of records. Being open to public means the contents of records should be interpreted for normal people to easily understand and be published in books or be on website. In other words, the whole contents of sahaeng-ilgi, poetry and prose, and letters along with all the poems of paintings and calligraphic works should be open to public through books or website after being interpreted. The meanings of documentary heritages are difficult to be conveyed without texts due to their characteristics. Therefore, institutions holding documentary heritages should secure budget and specialized manpower and immediately start text interpretation work. There might be differences according to the volume documentary heritages, but it takes a lot of time to interpret texts , so it is necessary to plan and start working urgently. It is important to open the images of documentary heritages to public , so that anyone can easily access and use them in various fields. Documentary heritages are our assets that we inherited from our ancestors, preserve and will bequeath to our descendents. Institutions holding them are the management authority rather than those who own, so they have obligation not only to preserve but also to share them. It is necessary to constantly plan and promote various exhibitions, education and academic programs, and cultural events with the theme of documentary heritages. The accessibility of documentary heritages can be enhanced when they are easily understood and spread widely. Furthermore, if institutions holding them plan and process these together, the synergy effect can be also expected. For this, there is a need to consider forming a consultative group. If a consultative group is formed , it is easy to get budget and experiences from government or UNESCO , and exchange and cooperation not only with domestic institutions but also with holding institutions in Japan can be reinforced.