Background and Purpose: Nowadays, we are facing an increasing number of known and unknown diseases that necessitate referral to the International Classification of Diseases (ICD). Despite the increasing global tendency to traditional and complementary medicine over the past decade and acceptance of Persian medicine (PM) by the international community, the disease titles of this school of medicine have unfortunately not yet found their place in ICD. This paper is a comparative study of head diseases in Persian medicine texts (2^nd to 15^th century AH) and equivalent chapters in the international classification of diseases.
 
Materials and Methods: This study was conducted qualitatively (content analysis) by studying Persian medicine reference books in several stages.
 
Results: After an overview of the books and introduction, the sources were arbitrarily arranged in three separate historical periods and in a separate file due to the large volume of data. Selected resources included thirteen books from the 2^nd-5^th centuries AH, seventeen books from the 5^th-10^th centuries AH, and eighteen books from the 10^th-15^th century AH. After examining the titles of diseases in the human body, head-related diseases were recorded separately and in tables of three time periods. Abbreviations of book names along with their arbitrary numbers in the first to third time periods were also extracted in a separate table. Then, the terms used in the texts of Iranian medicine were equated with the English terms of diseases, signs, and symptoms (modern medicine) according to Qamous al-Qanun, and mostly Iksir-i Azam. Codes were extracted from the ICD-10 book (2019 edition). Eventually, a list of nervous system diseases along with their equivalents in ICD headings 10 and matching English terms of head diseases in PM texts was prepared by using classification blocks.
 
Conclusion: The study of the surviving texts in the context of history makes it necessary to return to this ancient heritage and revive it in the context of new findings. A principled order and subset exist in the structure of classification of head diseases in Persian medical texts, which can be used in the context of data processing in the health system, development of national standard classifications, and expanding it to other diseases.