The percentage of obese individuals continues to grow worldwide, and the main factor leading to obesity is the imbalance of energy intake and consumption. The intestinal flora has important regulatory roles in metabolic disorders and obesity. Compared with normal-weight individuals, those that are obese showed remarkable changes in the composition of the intestinal flora. Several studies have reported that probiotics can reverse high-fat diet-induced obesity. Thus, altering the intestinal flora may be an effective approach to control or even prevent obesity, and some probiotics have been demonstrated to have effects on obesity. The purpose of this review is to summarize the experimental means used to study probiotics and obesity and to summarize the weight-loss effects and mechanisms of action of experimental and clinical probiotics, so as to help investigators understand the latest benefits of weight-loss probiotics and to provide a reference for follow-up research in this field.