Existentialism is one of the most important and influential philosophical and literary schools in the world, the birthplace of which is "Europe." Faced with the boundaries of "death, suffering, fear, and sin," these situations make one become aware of his innermost hidden dimensions, and to know himself better. Existentialism philosophy based its analysis of human destiny on three fundamental inferences and provided three signs of existence for it. The purpose of this article is to enlighten the three principles of existence (sensory, moral and faith) in my dog Atma.The results show that Chubak's worldview is influenced by philosophers' analysis. This author's stories are full of themes (death, suffering, fear, and sin). In the analysis of the story (Atma my dog), we came to the conclusion that the first character of the story reaches the stage of faith existence by passing through the stage of moral and moral existence.