Multiple sclerosis (MS) is a chronic autoimmune disease, and the most common cause of nontraumatic disability in young people. The etiology of this disease is not well defined yet. Cytoldnes play an important role in differentiation, maturation and survival of a wide range of cells, including cells of the immune system. Suppressor of cytokine signaling (SOCS) proteins are the most important regulators of this cytokine signaling pathway. The aim of present study was to compare the expression levels of SOCS1, SOCS2, SOCS3 and SOCS5 genes in the blood of 50 relapsing-remitting MS (RR-MS) patients and 50 healthy controls by Taciman Quantitative Real-Time PCR in patients and healthy control group. We observed that SOCS1 and SOCS5 expression was significantly down -regulated (P = 0.045 and P = 0.044, respectively); whereas, no significant difference was observed between MS patients and controls for SOCS2 and SOCS3 gene expression (P = 0.747 and P = 0.439, respectively). In addition, there was no significant correlation between the expression of SOCS1, SOCS2, SOCS3 and SOCS5 genes and clinical findings, such as the level of physical disability in the MS patients according to the Kurtzke Expanded Disability Status Scale (EDSS) criterion and disease duration. However, a significant positive correlation was observed between expression levels of SOCS genes. This study shows that loss of balance among various members of the SOCS family proteins may contribute to pathophysiology of -multiple sclerosis. (C) 2017 Elsevier B.V. All rights reserved.