Diabetes mellitus (DM) is a metabolic abnormality linked to a higher risk of heart disease and stroke. The objective of this research is to see how three extracts of Onopordum alexandrinum Boiss affect serum glucose and blood lipids in diabetic rats that have been given alloxan. For 21 days, 48 mature male Sprague-Dawely albino rats (125-135 g) were chosen at random and placed into six groups of eight animals each: (1) non-diabetic control group, (2) diabetic control group, (3) diabetic group + Glibenclamide (10 mg/kg body weight), (4) diabetic group + petroleum ether extract of O. alexandrinum (480 mg/kg body weight), (5) diabetic group + ethyl acetate extract of O. alexandrinum (420 mg/kg body weight), and (6) diabetic group + ethanol (70%) extract of O. alexandrinum (600 mg/kg body weight). Triglycerides(TG), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), very low-density lipoprotein (VLDL) and glucose levels were measured in the serum of all individuals at 0, 3, 7, 14, and 21 days. In comparison to the control group and diabetic control group, administration of 480, 420, and 600 mg/kg body weight of petroleum ether, ethyl acetate, and 70 % ethanol O. alexandrinum extracts resulted in significantly lower glucose, TC, TG, LDL-C, VLDL levels, and increased HDL levels (p<0.05). Histological evaluation of groups treated with different O. alexandrinum plant extracts revealed that the injured pancreas was reconstructed. These findings suggest that O. alexandrinum extracts had a substantial influence on blood lipids and glucose levels in diabetic rats at all doses, suggesting that they could be effective in preventing and treating diabetes.