The conceptualization of "written language" as linguistic object seems related to the empowerment of the discipline at the turn of the 20st century. While they set their object and their methods vis à vis the philology, these theorists of the language of the first half of the twentieth century are confronted with the problem of the status of written productions. How these linguists apprehend updating the language through writing? How do they characterize, or not, the "written language" as an autonomous field who require specific methods? This paper examines the concept of "written language" in a corpus theoretical writings in French of the early century. It focuses in particular on the status of this concept in the courses in general linguistics of Ferdinand de Saussure and in the stylistics of Charles Bally.