||Urban light pollution, which poses a threat to peopleâ€™s production, life, and physical and mental health, is becoming increasingly serious and gradually forms a new type of environmental pollution. In order to further analyse the hazards and causes of Chinaâ€™s urban light pollution and explore its legal governance measures, this study reviews foreign literature on hazards and causes of urban light pollution, summarizes the types and causes of the pollution in China, and provides specific control measures from the perspective of legal governance. Research results in the country and abroad show that light pollution is caused by development, which has a serious negative impact on the normal life of urban residents. The hazards of urban light pollution are manifested in four aspects, such as damaging human health, affecting the natural ecological environment, affecting normal operation of urban traffic, and causing serious waste of energy. Urban light pollution is caused by the lack of systematized urban building light source design work, excessive use of electronic products with the development of science and technology, weak public awareness of environmental protection, and the delay of laws and regulations. Some legal measures to control light pollution are presented as follows: Perfecting the administrative system and environmental supervision system in legislation, innovating the legislation system of light pollution prevention, formulating strict civil liability for light pollution, and further formulating a single law on light pollution control. The results of this study have important reference value for taking measures predictably to avoid the occurrence of light pollution during urban construction design, for the macro-control of urban planning and management departments, and for promoting the concept of urban environmental protection and energy conservation and sustainable urban development.