This study is aimed to evaluate the histomorphology of small intestine of Wistar rats exposed to Eliozu dumpsite leachate. The toxic effect of Eliozu dumpsite leachate has been studied, where the researcher has identified that the leachate has toxicological effects on some organ tissues like the blood, reproductive tracts and hormones, oxidative stress parameters and the cerebral cortex. Twenty-five female Wistar rats weighing between 120-140 g were obtained from the animal house unit of Faculty of Basic Medical Sciences, University of Port Harcourt, Nigeria. The rats were randomly assigned into five groups of five (5) rats in each group. Group 1 served as a control and orally received 1 ml of bottled water; group 2 orally received 1 ml of water from a borehole close to the dumpsite. Groups 3, 4 and 5 received 1 ml of 10%, 50%, and 100% leachate concentrations orally for 30 days. In the present study, an alteration in the histoarchitecture of the small intestine of the Eliozu dumpsite leachate treated animals was observed; the small intestine of the control group has shown normal intestinal histoarchitecture. The mucosa forms a series of finger-like villi, each showing lamina propria, blood capillaries etc. the simple columnar mucosal epithelium contains absorptive goblets cells, crypts of Liberkuhn in the mucosa and Brunner’s glands. It is concluded that exposure to the Eliozu dumpsite leachate and the consumption of the nearby borehole water with significant heavy metals and microorganism have caused the histopathological alterations in gastrointestinal tracts (small intestines) of animals and it is recommend that Government and environmental regulatory agencies find an ecofriendly method to treat Eliozu dumpsite leachate.