In the early 20th century, Cubism broke away from previous painting conventions and created a new era for Contemporary art. However, the revolutionary change brought about by Cubism is not restricted to the field of painting but it can also be present in various arts such as literature, film, architecture and music. The correlation between Cubism and literature first appeared in the area of poetry based on visual images. However, looking at the relevance of these from only this perspective would be only a very superficial simplification of this aesthetic, which has brought about some revolutionary changes in modern aesthetics. Cubism is based on a new epistemological view of the world. In this context, we will look at the background and principles of Cubism in the early 20th century and explore through the literature of Gomez de la Serna, the pioneer of the Spanish avant-garde movement, how the principles are deeply embedded in literary writing as well. We will identify and analyze these principles within his work entitled El teatro en soledad, published in 1912 but not widely known among scholars, but not without previously paying attention to the Cubist elements which crowd the literary that genre he created, his much-applauded greguerias. Theater within the theater technique and superposition, multiple viewpoints, simultaneity and collage will play an important role in revealing the important influence of Cubism on his works.