Present study was conducted to investigate the effects of cumin (Cuminum cyminum) essential oil on the intestine and liver tissues of zebra fish. Essential oil was added to the diet in two concentrations (500 and 1000 mg/kg) and at the end of the experiment (8 weeks) histological studies were performed. The results showed that villus height and width, absorption surface area of the intestinal mucous membrane surface, diameters of hepatocyte and their nucleus in the fish that fed with the essential oils were higher than control treatment, while the crypt depth decreased compared with the control. In fish grown with diet containing 1000 mg/kg, the number of goblet cells increased compared with control group, while in fish fed with the lower concentrations, the number of them was lower. Despite the observed changes in the measured parameters just the diameters of the hepatocytes in fish fed with diets containing 1000 mg/kg essential oils showed a significant difference and the size of these cells was larger than other treatments. In general, due to the increase in the absorption surface area and decrease in the number of goblet cells in fish fed with diet containing 500 mg/kg essential oil it seems that the use of low concentrations of essential oils can improve the histological characteristics of the digestive tract.