Introduction: Improvement of lipid abnormalities are important in the prevention of diabetes complications. The study aimed to determine the effect of nigella sativa oil extract oil on blood lipid abnormalities in patients with type 2 diabetes. Materials and Methods: In this double blind randomized clinical trial, 43 men and women with type 2 diabetes who were randomized to the intervention (n=23) and placebo (n=20) groups were studied and compared. The intervention group received 2 capsules daily, (500 mg extract of Black Seed Oil) while the control group took 2 capsules (500 mg, placebo daily) for 8 weeks, respectively. Lipid profiles were measured at the beginning and end of the inte­rvention. Result: Mean age and body mass index of participants was 53.7±6.0 y and 28.6±5.4 kg/m2, respectively. At the end of the eighth week, the concentrations of serum triglycerides, LDL cholesterol, total cholesterol and LDL to HDL cholesterol of the intervention group were compared to the placebo group, and a significant reduction (P<0.05) was found. However concentrations of HDL cholesterol and total cholesterol to HDL cholesterol ratio, at the of the end eighth week in the intervention group and the control group showed no significant difference. Conclusion: Black Seed Oil extract improves lipid profiles in type 2 diabetic patients.