Vitamin E is an important lipid-soluble antioxidant. The aim of the present study was to investigate the effect of curcumin on serum vitamin E levels in subjects with metabolic syndrome (MetS). A total of 120 subjects aged 18-65 years old with MetS were recruited in this study according to the International Diabetic Federation Criteria. Included subjects were randomized into three groups: subjects receiving lecithinized curcumin (1 g/day equivalent to 200-mg pure curcumin per day) for a period of 6 weeks) n = 40), patients receiving unformulated curcumin (1 g/day) for a period of 6 weeks) n = 40) and a control group receiving placebo for the same period (n = 40). Vitamin E was determined in all patients before and after the intervention using high-performance liquid chromatography method. Results showed that curcumin has no improving effect on serum levels of vitamin E (p >0.05). There were significant differences between pre-trial and post-trial levels of vitamin E/low-density lipoprotein cholesterol ratio (p < 0.05), vitamin E/high-density lipoprotein cholesterol ratio (p < 0.05), vitamin E/total cholesterol ratio (p < 0.01) and vitamin E/triglyceride ratio (p < 0.05) between the three groups of the study. Results of the present study did not suggest any improving effect of curcumin supplementation on serum vitamin E concentrations in subjects with MetS. Copyright (C) 2017 John Wiley & Sons, Ltd.