Non-alcoholic fatty liver disease (NAFLD)is the most common liver disease. Diet plays an essential role in the management of disease. Recently, antioxidant-rich food sources such as soy products have gain a great interest in improvement of NAFLD. However, up to now, no study has investigated the effect of soy milk consumption on NAFLD. Therefore, the aim of this study is to assess the effects of soy milk consumption on metabolic and inflammatory status as well liver steatosis in NAFLD patients. In this randomized clinical trial study,70 patients aged 18 to 60 years will randomly assigned to intervention or control group. Since this study is a dietary intervention, there is no blinding. Both two group follow a 500-calorie deficit diet for 8 weeks. In intervention group, one glass of soy milk ( 240 cc ) is replaced with one serving of both starches and fats groups based on dietary exchange list. While, patients in the control group not allowed to consume any forms of soy products or isoflavone supplements during the study.All laboratory test including liver enzymes, lipid profile, markers of oxidative stress and inflammation, glycemic status, in addition hepatic steatosis, blood pressure and anthropometric indices will be measured at baseline and week 8 of the study. Also, the dietary intakes and physical activity will be measured at baseline and end of the study.