Metiram is a fungicide used against fungal diseases of field crops. Nigella sativa L. ( Black seed) is a widely distributed herb with wide therapeutic uses. This work aims to study the effect of N. Sativa oil on ovarian toxicity induced by metiram fungicide in albino rats. Treating animals with metiram caused many histopathological alterations. The number of ovarian follicles decreased and most of them degenerated which accompanied by an increase of atretic follicles and an increase of collagen fibers. Histochemical results revealed a decrease in carbohydrates content. Metiram significantly decreased the levels of both LH, FSH, and estradiol. It also caused an increase in lipid peroxidation and decreased ovarian antioxidant enzymes, SOD, CAT. This study revealed The ameliorative effect of N.sativa oil against metiram -induced ovarian toxicity through a significant increase in the number of healthy follicles with a decrease of the atretic follicles and collagen fibers. Moreover, N.sativa treatment led to a significant increase in FSH, LH, and estradiol levels. A decrease in lipid peroxidation and an increase in antioxidant enzymes were recorded. These results give new insight on beneficial effect N. Sativa oil against female gonadal toxicity and this effect may be attributed to its antioxidant activity