This thesis revealed the core assertions and characteristics of the researchers along with the contents of the original texts on the three controversial issues in Sino-korean literary researches which had recently been presented. First, I studied about the poetic implication of ‘The secrets of nature’, a key issue in the literary theory. Kim Hye-sook and Lee Dong-whan explained the meaning of 'The temper性情' and 'The secrets of nature' which Nongam had said in ｢Jabji雜識｣, Lee Sung-soo and Lee Dong-whan defined the meaning of ‘The secrets of nature’ and ‘The law of nature天理’ which Samyeon had said in ｢Ilrok日錄｣. Second, I compared four theses which had analyzed ｢Yachoolgobookgoogi夜出古北口記｣ written by Yeonam. Lee Dong-whan and Kim Do-ryun analyzed this essay focused on 'the aspect of thought' and 'the artistic quality', Lee Sung-soo and Jung Kil-soo analyzed the essay focused on 'the structure and aesthetic senses' of it and 'the criticism by predecessors and the adaptation process'. Third, I compared three theses which had analyzed ｢Dablimhyungoronyuendosu答任亨五論原道書｣ known as Yeonam's later essay. Lim Hyung-taek explained the characteristics of Yeunam's ideas, mainly about the terms in the essay, with the point of view of dialectics. Park Hee-byung explained Yeonam's practical utterances for the society and reflections for person's inner life. Shin Hyang-lim proved that Yeonam's ideas had been affected by the doctrines of Wang Yang-Min. Like the above, in the core of the critical issues on the results of the Sino-Korean literary researches, there's philosophy problems related with literature. First of all, the notion of ‘The secrets of nature’ in ‘The discussion of the secrets of nature天機論’, which has placed in the center of the literary theory in the later period of Joseon Dynasty, was related with the core contents of the history of ideas in the period, such as 'Yinsimdosimsul人心道心說' and 'Yinmoolsungdongyiron人物性同異論'. ‘The secrets of nature’ which Nongam had said in ｢Jabji｣was used as the core notion in the literary theory, and 'The secrets of nature' Samyeon had said in ｢日錄｣ was used as the core concept in 'Yinsimdosimsul' and 'Yinmoolsungdongyiron'. In addition to it, the implication of ‘The temper’ in ‘The discussion of the temper性情論’ in literary theory was not unrelated with the implication of 'The temper’, the core concept of The Neo -Confucianism性理學. Also, in the background that the four theses which had analyzed ｢Yachoolgobookgoogi｣ reached the different conclusions, there's the difference of the analysis for Yeonam's ideas in it. Finally, the analysis about the epistemology and aesthetic senses for Yeon's work could be altered according to what his ideological base was. This study will be able to find the meaning at the point of confirming the fundamental learning principle that the understanding of the primary meaning of the original text is more important than anything else in Sino-Korean literary researches.