Osteoporosis and obesity are common diseases. But their relationship remains controversial. Evidence has shown that there is an association between bone mass and fat metabolism, and, some adipose tissue-secreted bioactive molecules, such as estrogen, resistin, leptin, adiponectin, IL-6 and so on, are involved in bone metabolism. What’s more, the regulation pathways which affect the differentiation of stem cells also mediate the occurrence of osteoporosis. In this article, we reviewed the role and mechanism of adipose tissue in the occurrence of osteoporosis.