The purpose of this study was to compare and analyze the inner principles of expression and formative language through self-portraits of Vincent van Gogh and Edvard Munch. The artists wanted to express the internal anxiety and frustration that they had experienced in their childhoods. While Van Gogh tried to prove his existence to others by depicting himself in a self-portrait drawn as a gaze at inner feelings, Munch tried to gain an objective insight into his present, unable to escape from the sadness of loss. When comparing the meaning and principle of inner expression based on the content and style of their self-portraits, the difference is shown in Van Gogh’s expression of eternal inner vitality and Munch’s expression of anxiety and fear. There was also a difference in the formative language analysis such as color and tone, matiere, light, space, the angle of vision, and size of the subject. Gogh uses bright yellow in contrast with blue as a means of expressing himself, and he asserts himself with strong matiere, plain light, a large-size portrait, and the subject’s clear eye-contact with the viewer. However, Munch contrasts red with black, using the dark tones as a symbol of death and anxiety, a flat matiere of intense touch, backlight, blurry eye contact, and a small-sized subject. These qualities express his internal conflict and his acceptance of his own problems with visual insight.