Objectives: The objective of this study is comparison of therapeutic effect of Melatonin, Metformin and Ursodeoxycholic acid with placebo in treatment of patients with Nonalcoholic Fatty Liver Disease (NAFLD). Design: Patients with NAFLD who have proven steatosis by Fibroscan, during the double-blind randomized clinical trials are under treatment regimen. Setting and conduct: Patients divided into three groups and one control group. This pilot study would be with a sample size of 120. For the patients at the beginning and end of the project weight, height, waist circumference, BMI, Cholesterol, TG, LDL, HDL, FBS, HbA1C, INR, PTT, PT, Billirubin (Total, Direct), Albumin, AST, ALT, ALK-P, CRP, the steatosis and hepatic fibrosis patients is measured. Exclusion criteria: Consumption more than 20 gram of alcohol per day for women or more than 30 gram in men for at least 3 consecutive months during five last years; people with hepatitis B,C; chronic liver disease; heart failure; consumer of osteoarthritis medications that cause hepatitis; proven diabetes mellitus; proven hemochromatosis and unwillingness to participate in the project. Intervention: This study will be a pilot study with 120 sample size. Patients enter one of four categories for three months: Intervention group 1: The group that received tabs Melatonin, 10 milligram, one number, daily (Manufacturing factory is Nachermed of America); Intervention group 2: Tab Metformin, 500 milligram, one number, every 12 hours (Manufacturing factory is Aria); Intervention Group 3: Cap Ursodeoxycholic acid, 300 milligram, one number, every 12 hours (Manufacturing factory is Sosefarm of Italia); Control group: Tab Placebo, one number, daily. Diet respected in all groups. At the end of the study, the frequency of existence statuses and fibrosis in patients each group based on the results of Fibro scan and also check liver enzyme levels and other tests will be calculated. Main outcome measures: primary outcome variables are the Body Mass Index and Serum levels of liver enzymes. Also, the secondary outcome variables are serum lipids and Body Mass Index respectively.