Satureja khuzestanica is an endemic plant of Iran that is widely distributed in the Southern part of the country. It has antioxidant properties and thus it seems to be useful in diseases related to oxidative stress such as diabetes and hyperlipidemia. The present study investigates the effect of S. khuzestanica supplement in metabolic parameters of hyperlipidemic patients with type 2 diabetes mellitus. Twenty-one hyperlipidemic patients with type 2 diabetes mellitus were randomized in a double blind, placebo controlled clinical trial to receive either S. khuzestanica (tablets contain 250 mg dried leaves) or placebo once a day for 60 days. Blood samples were obtained at baseline and at the end of the study. Samples were analyzed for levels of glucose, total cholesterol, LDL-cholesterol, HDL-cholesterol, triglyceride, creatinine, thiobarbituric acid reactive substances (TBARS) as marker of lipid peroxidation and ferric reducing ability (total antioxidant power, TAP). Treatment of patients by S. khuzestanica for 60 days induced significant decrease in total cholesterol (P = 0.008) and LDL-cholesterol (P = 0.03) while increased HDL-cholesterol (P = 0.02) and TAP (P = 0.007) in comparison with the baseline values. S. khuzestanica did not alter blood glucose, triglyceride, creatinin and TBARS levels. In comparison with baseline values, no significant change was observed in blood glucose, total cholesterol, LDL-cholesterol, HDL-cholesterol, triglyceride, creatinine, TBARS and TAP in placebo-treated group. Usage of S. khuzestanica as a supplement to drug regimen of diabetic type 2 patients with hyperlipidemia is recommended.