Abstract: Background and Objective: Gestational diabetes mellitus (GDM) seriously impairs the health of maternity and infant and it leads to pregnancy outcome. Antioxidants are matters that keep the cell injury caused by free radicals. Plants with antioxidant properties have been consumed for centuries as supportive therapy in the diabetes treatment. The present work was designed to assess effect of parsley extract on kidney of diabetic mellitus rats. Materials and Methods: Pregnant albino rats (n = 50) were divided after mating into five groups: First group (control group, C), second group (pregnant rats injected with intraperitoneal single dose of STZ (40 mg kg–1 b.wt.) in the 1st day of pregnancy (D1), third group: Pregnant rats were treated with parsley extract (1 m/150 g b.wt.) from the 1st to the 19th day of gestation post injection with STZ (40 mg kg–1 b.wt.) (D1+P), fourth group: Pregnant rats were injected with STZ (40 mg kg–1 b.wt.) on day 7 of gestation (D7), fifth group: Pregnant rats were treated with parsley extract (1 m/150 g b.wt.) from the 7th to the 19th day of gestation post injection with STZ (40 mg kg–1 b.wt.) (D7+P). The pregnant rats were dissected on the 19th day of gestation, any morphological or anatomical changes were photograph and blood sample were collected to estimate the hematological parameters. In addition, kidney samples of pregnant rats were taken for the histopathological study. Results: Diabetic rats showed some morphological and anatomical changes such as deep neck abscesses, cancer and bleeding in the lung. On the other hand, diabetic mothers, which were treated with parsley leaves extract showed normal morphological structure. According to the haematological and histopathological studies, the parsley leaf extract ameliorate the damage were occurred due to diabetes mellitus. Conclusion: Administration of the parsley extract has the ability to decrease the injury of hyperglycemia.