Background: Diabetes mellitus can lead to histomorphometrical changes in the brain. Recent studies have shown that Aloe vera gel has antioxidant and neuroprotective effects, which is independent of glucose-lowering effects. Objectives: The present study aimed to investigate the effects of A. vera gel on histomorphometrical changes of cerebellum following streptozotocin (STZ)-induced diabetic male rats. Methods: A total of 25 male Wistar rats were randomly allocated into five groups as follows: (1) the control group received normal saline; (2) A. vera gel group; (3) diabetic group; (4) treatment group diabetic rats, which received A. vera; and (5) diabetic rats which received insulin. A single dose of STZ [60 mg/kg; intraperitoneal (IP)] was used for the induction of diabetes in rats. All the treatments were administered daily for eight weeks. Subsequently, histomorphometrical changes were evaluated in the cerebellum of the rats. Results: The results showed that the number of granular and purkinje cells reduced in the cerebellum granulosa region, while the number of glial cells increased in the molecular region of the cerebellum in diabetic rats compared to the control group (P < 0.05). These changes were improved in treated rats by insulin or A. vera. Also, the thickness of molecular, purkinje, granular, and white matter layers at the apex of lobules and depth of sulcus in the diabetic group had a significant reduction compared to other groups (P < 0.001). Conclusions: Our results confirmed that improvement of the cerebellar tissue changes in diabetic rats following the use of A. vera gel is comparable to insulin. However, more investigations are required to determine the protective effects of A. vera gel against diabetes-induced cerebellum histomorphometrical changes.