Obesity, which results from dysregulated energy homeostasis due to excessive energy intake and/or reduced energy expenditure, has now become a rapidly increasing worldwide epidemic that seriously threatens people＇s health. How to prevent and treat obesity has become a major research focus for basic and clinic scientists in the metabolic research field. Recent studies have identified a new type of cells in the subcutaneous white adipose tissue that develop thermogenic functions under the conditions of cold stimulation. These brown fat-like cells, or beige cells, are different from classic white adipocytes that play a major role in the storage of lipids. Like brown adipocytes, beige adipocytes have thermogenic functions and are able to promote energy expenditure, suggesting they are an exciting target for the prevention and treatment of obesity and related metabolic diseases. In the current review, we will briefly summarize current findings on the functions of beige fat and the mechanisms regulating the beigeing process of white adipose tissue.