This paper deals with Kim Kwang-guk's life as a middle-class people (中人) and a collector of painting and calligraphy both of Korean and Chinese. It also explores some problems related to his painting collection, inscriptions, and calligraphy that have not been fully discussed before.*br* Kim Kwang-guk(1727-1797, sobriquet Seoknong) is one of the prominent collectors of painting and calligraphy in the late Choseon period. During his whole life, Kim had collected a large amount of art works including Chinese cartographic maps. Such an art collection was possible for him because he accumulated fortune by serving as a medicine-official(醫官) at the royal court as did his former generations.*br* Around 1786, Kim made the voluminous albums titled Seoknong hwawoen (石農畵苑, Paintings collected by Seoknong) which cover various subject matters done by his former and contemporary artists. On the other side, he also made the second album, Hwawoen sokjip (畵苑牘帖, Supplement of paintings of Seoknong hwawoen), which seems to be mounted in his late years because there are some examples worked by his contemporary painters after 1786. But this should be supported by documentary sources.*br* Despite his ardor for collecting, all works were scattered after his death, and now an estimated 120 pieces are known to us including those in Hwawoen pyoeljip(畵苑別集, Collection of paintings not included in Seoknong hwawoen), his third album of collection. These remained paintings are attached with Kim's inscriptions on the left side, and many of them were written by other persons such as his friends. This produces ambiguity in distinguishing which the real inscriptions written by him are. In this paper, the two inscriptions of Seokbong chinjeok (《石峰眞蹟》, Calligraphic Works by Seokbong) transmitted in Kim's family through generations and of Yi Kyeong-yun's (李慶胤, 1543-1611) Song'eum goil-do (〈松陰高逸圖〉, Lofty Mind under Pine Tree) that has Kim's inscription dated 1753, are supposed to be written by him. Now approximately eleven works that show his calligraphic style are known. His inscriptions are thought to be important because they give new information of artists who can be hardly found in official documents.*br* Kim Kwang-guk's taste for art influenced his two sons, Kim Chong-geon(金宗建, 1746-1811) and Kim Chong-gyeong(金宗敬, 1755-1818). Both occasionally wrote inscriptions on behalf of their father or acquired famous paintings for him. For the further research for Kim's influence on his contemporary artists, his whole collection should be reshaped by locating works now have been scattered.