In this paper I would like to explain – taking a history of the early Heian period as a background – the process of creation of national (i.e. Japanese) culture by the aristocracy who – since the An Lu-Shan’s Rebellion – could observe from the Japanese Archipelago the first symptoms of the decline of the Tang dynasty in China. The Japanese of the Heian period, who – from the Chinese perspective – “lived at the frontiers of culture” (see: Umehara Takeshi, 2001) while being almost perfectly bilingual , did not deny Chinese culture, but on the other hand, they adapted from it the best and the most suitable aspects for their artistic images. I would like to show that process of aesthetical adaptation on the basis of an analysis of the part of “The Tosa Diary”, which is called to be a representative literary work in the Japanese literature of the 10th century. I think that the so often mentioned eclecticism of the work was not Ki no Tsurayuki’s isamiashi, i.e. literary failure (see: Hagitani Boku, 2000). In this paper I would like to prove that “The Tosa Diary” is a completed and intentionally written literary work (with the most important goal to discuss with the Chinese culture of the Tang dynasty), and its eclecticism was rather a result of groping for new expressions and a new literary genre in the process of creation of national culture.