Although it is not performed as common as in humans, kidney transplantation is an effective treatment option for end-stage renal failure in dogs and cats. Ischemia/reperfusion injury is an inevitable result of kidney transplantation and it may cause delayed graft function that leads to a reduction in the longevity of allograft. In this study we aimed to evaluate the effects of Morinda citrifolia derived fruit juice on post-autotransplant ischemia/reperfusion injury. Twenty four adult, male Spraque-Dawley rats weighing 300-350 g were used. The rats were randomly divided into three groups of eight each. Rats in the Control Group were orally administered with saline solution (0.5 ml/day), for 7 days. Rats in M1 Group were orally administered with morinda citrifolia fruit juice (Alnoni, Hanojou-Europe Ltd, Dinxperlo, Holland), 0.5 ml/day, for 7 days whereas rats in M2 Group were orally administered with the same morinda citrifolia fruit juice (1 ml/day), for 7 days. In the 8th day, rats were anesthetized and orthotopic unilateral renal autotransplantation was performed. Rats were euthanized after 24 hour reperfusion and ischemic kidneys were sent for histopathological examination. Formalin-fixed paraffin-embedded tissue sections were evaluated and scored according to the parameters of tubular brush border loss, mononuclear cell infiltration, degeneration, hyalin formation in tubul lumens, thrombosis and tubular necrosis. Mononuclear cell infiltration in M2 group was found to be significantly different (P<0.05) than those of Control and M1 groups. Thrombosis was not observed in any of the histopathological sections. As a result, a significant improving effect on the ischemia/reperfusion injury of Morinda citrifolia fruit juice was not determined in rats after renal autotransplantation. Keywords: Autotransplantation, ischemia, kidney, morinda citrifolia, reperfusion.