The purpose of the article is to study the aesthetic principles of expressionism that influenced the development of modern architecture. An analysis of the concepts and means of artistic expression of the direction under study is proposed. The conditions for the emergence and formation of expressionism, its artistic methods of expression from conventionally realistic to abstract, as well as the manifestation of this direction of art in architectural design are considered. A brief analysis of the connection between expressionism and other parallel trends or movements of art of the twentieth century is given. Variations of expressionism from the standpoint of abstract art are identified, where the search for interactivity between the artist and the viewer in the process of visual perception of the painting is indicated. It is concluded that imagination is one of the main ways of artistic thinking in the process of author’s artistic design. The manifestation of the aesthetic principles of expressionism in the architecture of individual countries is considered. It has been revealed that expressionism in architecture is characterized by a departure from traditional forms in order to achieve the maximum emotional impact on the recipient. The study of the stated topic allows us to draw a conclusion about the relevance of expressionism at the beginning of the 21st century, which, with its traditions, continues the achievements of expressionism of the 20th century. and at the same time gives a new impetus to artistic expressions of the personal views of artists and architects on the ongoing processes in society. Parallels of the beginning of the 20th – beginning of the 21st centuries. revealed similarities in the aesthetic principles of the formation of the subject-spatial architectural environment. Expressionist techniques, means and methods of working on a painting or object are most accurately able to express the feelings of artists and architects, their psychological stress, the conviction that the viewer must go through a new experience while looking at an architectural or artistic work.