Hydrogen is colorless and odorless small molecule gas with biological activity, and it can react with reactive oxygen species. It is believed that hydrogen has biological effects such as anti-oxidation, anti-inflammation and anti-apoptosis, and has extremely high biosafety. Recently, hydrogen application has been involved in various acute and chronic diseases, and benign and malignant diseases. In addition, means of hydrogen utilization is also enriched, including hydrogen inhalation, hydrogen-rich water drinking, intravenous injection or partial use of hydrogen-rich saline and dialysis of hydrogen-rich dialysate. More importantly, the increasing hydrogen-related clinical studies have further demonstrated that hydrogen is effective and safe for diseases. However, the molecular mechanism of hydrogen biological effects is not very clear, and many scholars and the general public lack an understanding of hydrogen development status, which limits the development of hydrogen medicine and the related products. The research and popularization of hydrogen medicine is still a work in progress.