Background and Aim: The theory of criminal personality is one of the new theories of criminology. Leaders of this theory believe that the four characteristics of "selfishness", "instability", "aggression" and "emotional indifference" are the constituent elements of criminal personality, and if these four characteristics are controlled, the likelihood of committing a crime is reduced.
Materials and Methods: The research method in this paper is descriptive-analytical.
Ethical Considerations: Honesty and confidentiality have been observed.
Findings: Saadi, as a famous poet and writer of the seventh century in Iran, in his literary texts by examining these four elements, deals with its effect on the personality of individuals.  In Saadi's books, one can find a close connection with criminological theories. Saadi, like a criminologist, tries to express the factors of people's tendency to anomalies and anti-social behaviors in the form of rhythmic poetry and prose. "Selfishness", "instability", "aggression" and "emotional indifference" have a special place in his words.
Conclusion: This article shows that the theory of criminal personality - like many theories of modern scientists in the West - was expressed many years ago in Iranian literary texts, especially in the books of Saadi Shirazi.

Please Cite This Article As: Rahmat, MR & Nezaminia, S (2021). “The Theory of Criminal Personality in Saadi Shirazi's Books”. Interdisciplinary Legal Research, 2 (1): 69- 84.