Abstract: The article deals with the peculiarity of the diary genre (gaining popularity since the era of sentimentalism), which belongs to the world of ego-literature. The main features of this genre are summarized, the specifics of the writer's diary are emphasized. The main attention in the work is focused on the phenomenon of V. K. Kuchelbecker's "Diary", a bright representative of Russian Romanticism, connected with the Decembrist movement. Accordingly, the research material is "Diary" by V. K. Kuchelbecker, over which the author worked while in solitary confinement, and later in Siberian exile, from 1831 to 1846. The main issues that Kuchelbecker contemplates in his "Diary" are considered. The novelty of the research lies in the new perspective of consideration of Kuchelbecker's little-studied work, the research interest in this text first appeared only in the late 20s of the 20th century). The author demonstrates an unusual attitude and perception of time - present, past and future, shows a complex relationship between the private (personal) and the general (in social and historical aspects), considers the interlacing of micro and macro history, personal life circumstances and the macro-historical narrative in this work. The narrator of the Diary is shown as a representative of the world of the Decembrists, as a kind of their "voice". The work uses the methods of the historiosophic analysis of artistic works and implements the principles of the historical-typological method. Behind the seeming kaleidoscope of plots and images of the Diary is the subordination of the text to the general idea - to convey a sense of the post-December era.