Abstract: The quasi-impossible world of art is a new deduction within the scope of the "possible world". The principle of the "possible world" discussed in General Narratology interprets and explains how a narrative text can shuttle between the real, the possible and the impossible world in the way of human culture. The quasi-impossible world of art can be divided into the "relatively abnormal anti-common sense world" and the "absolute logic-impossible world", corresponding to adynaton and oxymoron. The union of both rhetorical devices into the art-impossible world can largely cover the quasi-impossible scope we discussed, helping to deduce from the humanistic perspective and unfold the endless map of the quasi-impossible world of art in detail. The introduction of theory of accessibility facilitates an in-depth analysis of the endowment and characteristics of the quasi-impossible world of art, while disentangling the relationship between literary artistic fiction and reality, and examining the essential difference between documentary and fictional narratives.