Objective:To analyze the hotspots and frontiers of hyperbaric oxygen（HBO）research in and out of China.Methods:HBO-related articles published on CNKI and Web of Science from January 1，2010 to December 31，2020 were analyzed by CiteSpace from the following aspects such as the country，institution，author，and high-frequency key words，etc.Results:The study included 9，911 Chinese and 5，193 English literature. The knowledge mapping analysis showed that the HBO departments in Chinese hospitals were currently the main institutions in contributing Chinese articles on HBO，with few close collaborations among them；there were three relatively large HBO research teams in China，and the co-authorship within each team was common，while the cooperation between teams was not so close. The US had the most HBO-related articles published in English，followed by China and Turkey，and the articles published in the US had the strongest centrality in the map. The authors of English articles mainly came from five research teams，with relatively close cooperation within and among the teams. Key words co-occurrence and cluster analyses of Chinese articles showed that the research hotspot was applied research on the therapeutic evaluation of HBO in the treatment of various diseases，such as CO poisoning，sudden deafness，cerebral infarction，severe craniocerebral injury，delayed encephalopathy，cerebral hemorrhage，diabetic foot，hypoxic-ischemic encephalopathy，brain edema，etc. Key words co-occurrence and cluster analyses of English articles showed that the hot topics included basic experimental research on HBO mechanism，such as oxidative stress，expression，and apoptosis，and research on clinical application of HBO therapy in radiation injuries from cancer treatment，cerebral ischemia，decompression sickness，CO poisoning，traumatic brain injury，stroke，and diabetic foot ulcer，etc.Conclusion:Research focuses of HBO in and out of China were not completely same. In China，researchers focus on clinical application of HBO，while out of China，basic experimental research on HBO receives more attention.

Objective:To analyze the hotspots and frontiers of hyperbaric oxygen（HBO）research in and out of China.Methods:HBO-related articles published on CNKI and Web of Science from January 1，2010 to December 31，2020 were analyzed by CiteSpace from the following aspects such as the country，institution，author，and high-frequency key words，etc.Results:The study included 9，911 Chinese and 5，193 English literature. The knowledge mapping analysis showed that the HBO departments in Chinese hospitals were currently the main institutions in contributing Chinese articles on HBO，with few close collaborations among them；there were three relatively large HBO research teams in China，and the co-authorship within each team was common，while the cooperation between teams was not so close. The US had the most HBO-related articles published in English，followed by China and Turkey，and the articles published in the US had the strongest centrality in the map. The authors of English articles mainly came from five research teams，with relatively close cooperation within and among the teams. Key words co-occurrence and cluster analyses of Chinese articles showed that the research hotspot was applied research on the therapeutic evaluation of HBO in the treatment of various diseases，such as CO poisoning，sudden deafness，cerebral infarction，severe craniocerebral injury，delayed encephalopathy，cerebral hemorrhage，diabetic foot，hypoxic-ischemic encephalopathy，brain edema，etc. Key words co-occurrence and cluster analyses of English articles showed that the hot topics included basic experimental research on HBO mechanism，such as oxidative stress，expression，and apoptosis，and research on clinical application of HBO therapy in radiation injuries from cancer treatment，cerebral ischemia，decompression sickness，CO poisoning，traumatic brain injury，stroke，and diabetic foot ulcer，etc.Conclusion:Research focuses of HBO in and out of China were not completely same. In China，researchers focus on clinical application of HBO，while out of China，basic experimental research on HBO receives more attention.