Late-onset hypogonadism (LOH) refers to the decline in serum testosterone levels in middle-aged and elderly men with aging, causing symptoms such as decreased libido, erectile dysfunction, and reduced physical and mental activity, as well as metabolic abnormalities such as abdominal obesity, diabetes and myopenia. The diagnosis and treatment of LOH are closely related to the health and quality of life of middle-aged and elderly men. It has been a focus of medical attention. The clinical data over the past decade provide substantial evidence for these issues. Consequently, Growth and Development and Gonadal Diseases Committee of Chinese Aging Well Association organized 52 experts in endocrinology, andrology, urology, geriatrics, traditional Chinese medicine, nutrition, laboratory medicine, cardiology, neurology, psychiatrics, hematology, orthopedics, basic medicine, pharmacology and othe fields. Based on the Oxford Center for Evidence-Based Medicine's level of clinical evidence and recommendation levels, the guidelines have been developed around the diagnosis of LOH, the risks and benefits of testosterone supplementation. Combined with the evaluation opinions of Delphi method, 17 recommendations were finally formulated to help clinicians cope with LOH.