In 1636, Jeon-hyeong, who visited Japan as a Neungseogwan, left a record of his diplomatic experience on the recommendation of vice envoy Kim Se-ryeom. Byeongja Haesa Ilgi(丙子海槎日記) under the title of Jeonjinsa Haesa(全 進士東槎錄日記) was handed down to the descendants' families. If you look up early 17th century records, there are hardly to find any diplomatic records except for 『Haehaeng Chongjae』. Additionally, according to the atmosphere of the age, the author was mainly comprised of emissaries such as senior emissary, vice emissary and third emissary. Therefore, in case of 『Haesa Ilgi』 written by Jeon-hyeong who had played a roll in a Neungseo-gwan not an emissary was very rare to exist. Given some factors, as follows, the position of Neungseogwan seems to have been established temporarily to assist Kim Se-ryeom's diplomatic work called Tongsin Sahaeng in 1636. There are four factors could find out. First, Kim Se-ryeom sent several letters asking to go with him for Tongsin Sahaeng. Second, Jeon-hyeong had considered participating in diplomacy until he met Kim Se-ryeom in Busan on October first. Third, he told Soin Wada, Japaenese literati, his position as a man following Kim Se-ryeom. Fourth, he responded relatively freely to Japanese literati except for Kim Se-ryeom's orders. Comparing Jeon-hyeong's record with Kim Se-ryeom's one in general, the contents are similar, but Jeon-hyeong's one is more detailed. He would had been possible to observe and record more deeply because he was more freedom than any emissaries when it comes to meet Japanese literati and observe the surroundings. Therefore, Jeon-hyeong's record helps those diplomatic records to supplement more plentifully. For Jeon-hyeong, Tongsin Sahaeng gave an opportunity to broaden the friendship with government officials. Therefore, not only the observation of Japan, but also the Joseon who dispatched together became as an interested object and a observing target. 『Haesa Ilgi』 is a vivid record, which experienced as a member of Sahaeng-won not as an emissary, that shows the reality of diplomacy.