The importance of corpus-based studies is gradually increasing in terms of foreign language education. The priorities of the words taught in language education are determined within the framework of international criteria through corpus-based studies. Corps and subcollections consisting of many layers such as written texts and speeches increase the efficiency of the process for both the instructor and the student. Teaching Turkish as a foreign language generally focuses on the vocabulary of course materials. The vocabulary of learning individuals is one of the areas that should be focused on for researchers in this process. Written or oral vocabulary of individuals learning Turkish as a foreign language is observed both to see the current situation and to make comparisons with frequency lists. The texts within the textbooks are the roof for the curriculum and the instructor. In this study, the written vocabulary of B1 level students learning Turkish as a foreign language, the vocabulary of the reading texts of the materials used in the lesson and Aksan (2017) corpus-based study constitute the focus of the study. 7 different compositions were written to 21 students during the 6-week B1 course. Subsequently, these compositions were transferred to computer environment in order to determine the students' written vocabulary; The reading texts in the textbook used have been made suitable for the software to be used in determining the vocabulary by passing through the relevant stages. The most frequently used 500 words in the vocabulary of the textbook and the written expressions of the students were compared with the work of Aksan (2017), the 500 words most frequently used in terms of word types, and their level of similarity was determined. In terms of the most frequently used words, it was determined with the corpus-based study of Aksan (2017) that the vocabulary of the course material was not at the desired ideal level in terms of similarity level.