The most important claim of the traditionalists about calligraphy is the semantic field or encryption. This essay’s primary purpose is to investigate the cryptographic basis of calligraphy from the perspective of the traditionalists. The study is an attempt to examine what is the semantic field and encoding of calligraphy from the perspective of traditionalists,? Moreover, what does this basis have to do with tradition? This research assumes that the science of letters is the basis of calligraphy encryption from a traditionalist’s perspective. The research method is descriptive and analytical, and the attempt is to look at the basis of cryptography in traditionalists’ writings such as Seyed Hossein Nasr, Titus Burkhardt, and Shuan and Guenon. The first part discusses the basis of traditionalists’ encryption and their claims about the calligraphy somatic according to their writings. The essay’s second part studies the encryption of traditionalist’s basis (the science of letters) in Islamic sources. The traditionalists consider the meaning of language letters in calligraphy, and calligraphic encoding is related to the language letters and Jafr (science of letters) and not necessarily the calligraphic aesthetic aspect. This encryption is more of a linguistic phenomenon (related to letters) than calligraphy. At the same time, the essay’s second part shows that the science of letters basis is contradictory, and Islamic sources mostly reject the science of letters basis. As a result, traditionalists’ encryption claims in the calligraphy need to be validated.