Known as a representative of the school of American Realism, Edward Hopper has made a substantial impact on American art and pop culture, including the film industry. The works of Edward Hopper are known to demonstrate a sense of alienation among subjects. His subjects usually appear with a sense of loneliness, even when they are not physically alone. This essay attempts to explore the causes behind the sense of alienation conveyed in Hoppers paintings. The study of alienation has a long history, and this analysis focuses on a more modern context. Thus, alienation will be discussed as a product of urbanization and industrialization. Alienation results from both external and internal causes; external causes emerge from the social milieu of the late 19th and 20th century, while internal causes originate from Hoppers life experiences. Additionally, this essay also analyzes the different manifestations of alienation in the works of Edward Hopper through selected works, such as Soir Bleu, Room in New York, Office in a Small City, etc.