Abstract: As a novel ultraviolet (UV) disinfection and sterilization technology, 222-nm UV irradiation can efficiently kill various microorganisms in the air and on object surfaces, while also demonstrating good biological safety for humans. This paper focuses on reviewing and introducing the recent progress at home and abroad regarding the disinfection efficacy, biological safety and practical application cases of 222-nm ultraviolet C. It elucidates that 222-nm UV has the potential to serve as an alternative and upgraded product to traditional 254-nm UV lights, expanding the range of application scenarios for traditional UV disinfection technologies. The consistency and reliability evaluation of the disinfection efficacy and biological safety of 222-nm UV in real-world environments still require more standardized experiments for verification.