Non-alcoholic fatty liver disease (NAFLD) has become a public health burden. Controlling bile acids (BAs) metabolism and energy expenditure are potential therapies for NAFLD. Because one of the main health effects of cereal β-glucan (BG) is its ability to lower cholesterol by interacting with BAs, BG may regulate imbalances of the metabolism of BAs during NAFLD. Therefore, by using metabolic tests coupled with the profiling of hepatic BAs, we have assessed the effect of BG from highland barley on western diet (WD) induced NAFLD mice. BG treatment prevented fat accumulation and increased adipose lipolysis. These moderating effects were associated with an increased energy expenditure. Moreover, BG-treated mice enhanced the production of hepatic BAs, which may be connected with the activation of farnesoid X receptor (FXR) signaling in the liver and inhibition of FXR signaling in the ileum. Our results suggest that BG prevents fat accumulation by increasing energy expenditure, a mechanism associated with major changes in the composition of hepatic BAs.