Objective. To evaluate the effectiveness of comprehensive treatment of patients with postoperative hypothyroidism (PH) and non-alcoholic fatty liver disease (NAFLD). Materials and methods. 40 patients (20 men and 20 women) aged 42±6 years with PH and NAFLD were examined. Patients were divided into two groups: main (n=20) and control (n=20). Prior to the study and after 1 month, the level of total cholesterol (TH), triglycerides (TG), low-density lipoprotein (LDL), alanine aminotransferase (ALT), aspartate aminotransferase (AST) was determined. Patients in both groups were prescribed levothyroxine sodium (125-175 μg a day). Additionally, the 1st group of patients received arginine hydrochloride 42 mg/ml according to the scheme 200 ml a day per 15 days, the next 15 days L-arginine aspartate 200 mg/ml 5 ml a day. And the control group received only levothyroxine sodium. Results. The level of TH in 1st group decreased from 7.1±0.8 to 6.7±0.4 mmol/l, and in 2nd – from 7.2±0.7 to 6.97±0.35 mmol/l. In the 1st group TG decreased from 3.9±0.4 to 3.5±0.3 mmol/l, and in the 2nd – from 3.8±0.5 to 3.7±0.1 mmol/l. LDL in 1st group decreased from 5.9±1.4 to 5.5±1.2 mmol/l, in the 2nd – from 5.8±1.3 to 5.7±1.4 mmol/l. The level of ALT in 1st group decreased from 47.5±1.82 to 40.1±1.73 IU/l, the level of AST – from 41.3±1.52 to 39.8±1.33 IU/l, in no changes in AST and ALT levels were observed in the control group. Conclusions. Comprehensive treatment of patients with PH and NAFLD contributed to the improvement of liver transaminases (reduction of AST, ALT), as well as the normalization of the lipid profile (reduction of TC, TG and LDL).