The aim of the present study is to elucidate the anti-obesity effects of Doenjang with and without salt in C57BL/6J mice. For the analysis, a total of forty mice were randomly divided into four groups: normal diet group (ND), high-fat diet group (HD), high-fat diet supplemented with 20% Doenjang group (DJ), high-fat diet supplemented with 20% unsalted Doenjang group (NS). During the study period, food intake and body weight were measured daily and weekly, respectively. The animals were sacrificed after 12 weeks. Body weight gain, epididymal fat pad weight and serum triglyceride levels of DJ group were found to be significantly lower than those of the HD and NS groups. Serum total-cholesterol levels of DJ and NS groups were significantly lower as compared to the HD group. There were significant decreases in plasma insulin and leptin levels in DJ group compared with the HD and NS groups. We did not observe any significant changes in the expression of hepatic lipogenic-related gene $PPAR{gamma}$ among the HD, DJ and NS groups. However, ACC expression was found to be significantly decreased in DJ group. Lipolysis-related gene ($PPAR{alpha}$ and CPT-1) expression was significantly higher in the DJ group as compared to HD and NS groups. In conclusion, the results of this study showed that Doenjang supplementation lowers body weight gain and improves obesity-related parameters.