Ji-u-jae (之又齋) Jeong Su-yeong (鄭遂榮) was a literati painter, active, during the Joseon Dynasty (1392-1909) from the late 18th to early 19th century. His ancestral home was Hadong (河東), and he used Su-dae (遂大) as his childhood name, Gun-bang (君芳) as his Ja (字), and Ji-u-jae (之又齋) as his pen name (號). Jeong Su-yeong began to gain attention his "Album Leaves of Sea and Mountain (海山帖)"was introduced by Choe Sun-wu (崔淳雨) in 1976. Furthermore, his life and family lineage were discovered by Lee Tae-ho (李泰浩) in 1984. Since then, He has been discussed as one of the important painters in the late Joseon dynasty in studies of "true-view landscape painting (眞景山水)" and literati painting, etc. However, attention has mainly been given to limited number of his most representative works and "true-view landscape painting". Thus, his friendship apart from his family lineage, or general painting style has rarely been researched. This paper, firstly, will study his rarely known life taking former research into consideration. Then, it will examine his painting subjects, the origin of its style, and distinctive features in general, focusing on landscape paintings still extant. Jeong Su-yeong was from 'The School of Practical Learning (實學)' of the Southerners (南人). Hence, he spent much of his lifetime making maps and working within family tradition compiling the genealogy for example. On the other hand, he studied poetry, calligraphy, and painting, and travelled widely. He, like his ancestors. mainly made friends with the Southerners, such as, Yeoju Yi clan (驪州李氏), Jinju Gang Clan (晋州姜氏), Dongbok O clan (同福吳氏), and Pungcheon Yim clan (豊川任氏). His experience in making maps is dearly connected with the fine brush works in his landscape paintings, the careful maimer and the broad point of view in his true-view landscape paintings, and the fact that he always indicated the place names on his paintings. Jeong entered the painting circle practising and copying Chinese painting manuals, such as "Splendid Scenery nationwide (海內寄觀)", "Paintings of Three Entities (三才圖會)", and "Paintings of Famous Mountains (名山圖)" as well as "Tang Poetry Painting Manual (唐詩畵譜)", "Mr. Ku Painting Manual (顧氏畵譜)", and "Mustard Seed Garden Painting Manual (芥子園畵傳)". Among them, the Ming woodblock print, "Paintings of Famous Mountains", was introduced in Joseon during the early 18th century, and was studied at first by Jeong Seon (鄭敾), Gim Hong-do (金弘道) and Jeong Su-yeong in the late 18th century, and later Han Yong-gan (韓用幹) and other Joseon scholars and painters through the 19th century. Moreover, Jeong was deeply interested in the Chinese Southern School painters (南宗畵家), such as, four Yuan masters (元四大家) and Ming's Wu School (明代吳派). Jeong's paintings can largely be divided into the fixed forms of paintings (定型山水), like Southern School style, and true-view landscape paintings (眞景山水). Both styles, however, had been developed in his paintings interweavedly since his 50's. His fixed forms of painting style, taking scholarly leisure culture as its background, is based on the Southern school style widely spread among contemporary painters. However, he was consistent to use a cursive brush with a stubby brush or a light ink, rather than systematic brush works. Furthermore, he evoked a unique atmosphere with his usage of light colors. The characteristic outline, which is thinly continued ill the expression of mountains and rocks, became a main element of Jeong's landscape painting. Jeong's true-view landscape painting, divided into paintings of Han liver (漢江) and Yim-jin river (臨津江), and Geumgang mountain (金剛山), shows relatively an adventurous features ill the following ways : the positiveness in directly sketching or completing the scenes on the spot, the way he drastically controlled its size according to object, the frankness which he reflected his own feeling, the attitude of using Korean place name in the vernacular on plane and geometric scenes or a title and an epilogue without hesitation. These characteristics became the key point in completing his true-view landscape painting, which succeed true-view landscape painting of the literati, the main painting stream in the 18th century. As seen above, Jeong's landscape painting, which depicts his individual point of view not restricted to a certain pattern and his own painting style, is a successful example of Joseonized painting, harmonizing literati culture and painting ability.