Purpose of Review <p>To elucidate the association between testosterone and skeletal health in men. In this review, i) we discuss the influence of testosterone on bone metabolism, ii) review population studies demonstrating the relationship between sex steroid concentrations and bone mineral density (BMD) and bone quality, and iii) summarize data from seminal trials of testosterone therapy and its effects on bone density and fracture risk.</p> Recent Findings <p>In population studies, low testosterone (and estradiol) levels in men are associated with reduced bone mass and a higher risk of fracture. Clinical studies of testosterone replacement in men with organic hypogonadism show robust improvement in BMD. To the contrary, clinical trials of testosterone therapy in middle aged and older men with age-related low testosterone have shown modest increases in BMD (mainly vertebral BMD). Results of the TRAVERSE trial unexpectedly showed higher fracture rates in men randomized to testosterone therapy.</p> Summary <p>Testosterone plays an important role in the maintenance of male skeleton. Most studies of testosterone therapy have demonstrated some degree of improvement in BMD, However, considering that testosterone treatment has not demonstrated reduction in fracture rates, we recommend that hypogonadal men who are at high risk for fracture receive treatment with agents that have proven anti-fracture efficacy.</p>