The book analyzes the concept of negative dialectics of Theodor Adorno, a theorist of the Frankfurt School, one of the major thinkers of the 20th century, based on the consideration of his texts, attracting extensive historical and philosophical material, including for the first time introduced into scientific circulation. Analyzing in depth Adorno's critical theory from dialectical-materialistic positions, the author compares two of its interpretations: traditional, representing negative dialectics in the form of total denial, the theoretical basis of the extremist movement of the new left, and new, considering Adorno's theory as an interesting project of a non-trivial type of philosophizing, oriented to aesthetics and having a relevant meaning in modern conditions.