Ｏｂｊｅｃｔｉｖｅ　 Comparing the effects of nasal catheter high-flow oxygenation with the effects of atomizing mask oxygenation on pulmonary oxygenation and cardiac function in patients who accepted CPB operation.　Methods　Sixty patients with intensive care unit undergoing CPB were randomly divided into high-flow oxygen group (experimental group) and traditional facial mask oxygen group (control group) according to the random number table method. Each group includes 30 patients. Two groups were treated equally according to the routine clinical measures after CPB. After extubation, the experimental group was assisted by high-flow oxygen inhalation humidifier, the control group was ventilated by oxygen inhalation. Cardiopulmonary function, clinical manifestations, use of vasoactive drugs, rate of secondary intubation and hospital stay were observed in both groups. Also blood gas analysis and related laboratory tests were performed.　Results　In the experimental group, oxygenation index, partial pressure of oxygen, length of hospital stay, brain natriuretic peptide (BNP) and cTnT were better than the values of the control group. The difference was statistically significant (P＜0.05). There was no significant difference between the experimental group and the control group on staying time in ICU and re-intubation rate (P＞0.05).　Conclusions　Compare with atomizing mask oxygen, nasal catheter high-flow oxygen can significantly improve cardiac function after CPB, effectively prevent the occurrence of pulmonary complications and improve oxygenation ability of patients.