Background: When a person suffers from obsessive-compulsive disorder (OCD), they experience intrusive and disturbing thoughts about specific topics (known as "obsessions") or feelings of compulsion to perform specific behaviors (known as "compulsions"). There is mounting evidence that dietary folate and vitamin B12 are crucial to the normal and abnormal functioning of the neuropsychiatric system. Studies on the incidence of neuropsychiatric symptoms in patients deficient in vitamin B12 have been conducted all over the world. Folate and vitamin B12 have lately been described in a substantial amount of literature as therapy or supplements for the management of psychiatric diseases. Aim of work: Shedding the light on the role of vitamin b12 and folic acid in OCD cases hoping to improve lately the assessment of symptoms severity and thus reducing the morbidity and mortality rates. Methods: Our research was a review article, interpreted in Al-Azazy Mental Health and Addiction Treatment Hospital during the period from august 2022 till January 2023. The Zagazig University IRB (ZU-IRB #9456/10-4-2022) was contacted for approval. We compiled and evaluated data from a wide range of relevant studies before writing a narrative review of our findings. Conclusion: We came to the conclusion that certain neuropsychiatric illnesses, such as OCD, can be correlated with vitamin B12 and folic acid levels. We suggest keeping a close eye on this phenomenon, which has to be investigated further. Our results can be used as a jumping off point for related studies.