Tramadol is a centrally acting opioid analgesic that used to relief pain. Although tramadol is thought to have low dependence potentials, it is used in acute or chronic pain., including postoperative, gynecologic and obstetric pain, as well as pain of various other Its uptake can lead to bad effects on the nervous system. Aim of the work: To determine the harmful effects of tramadol on the cerebellar cortex of adult male rats, as well as the potential ameliorative impact of thyme when combined with tramadol. Material and Methods: A twenty one adult male albino rats were randomized into 3 groups equally: The control group (group A) which was not received any medications, the tramadol group which was received tramadol HCL (40 mg/Kg/day) dissolved in tab water orally and the tramadol + thyme group (group C) which was received tramadol (40 mg/Kg/day) + thyme extract (500 mg/kg/day) orally. The tramadol and thyme were given to the rats for 8 weeks. Then the cerebella of the rats were processed to evaluate the histological, ultrastructural, immunohistochemical changes and morphometric analysis. Results: Histologically, ultrastructurally and immunohistochemistry, the group treated with tramadol revealed remarkable degenerative and neuronal apoptotic changes of the three layers of the cerebellar cortex especially the Purkinje and the granular layers. The group treated with tramadol + thyme showed improvement in the histological, ultrastructural and immunohistochemical changes. The morphometric analysis of the present study revealed a significant difference among the three groups. Conclusion: Tramadol intake exerted a neurotoxic effect on the structure of the cerebellar cortex of the adult male rats. Thyme extract can improve the tramadol effects but not repair it completely so this may be helpful in the management of the tramadol neuronal damage if the use of tramadol is necessary.