Objective：To investigate the therapeutic effect of high-flow nasal cannula（HFNC） oxygen therapy after thoracotomy in patients with acute hypoxaemic respiratory failure（AHRF）. Methods：A total of 53 patients who received thoracotomy in our hospital from January 1，2016 to December 31，2017 and had AHRF after discharging from ICU were retrospectively analyzed and divided into the general oxygen therapy group（n=31） and HFNC group（n=22）. Saturation of peripheral oxygen（SpO2），heart rate（HR） and respiration rate（RR） both before and after treatment were recorded at 2，12，48 h；indicators such as pharyngalgia/rhinodynia incidence，re-intubation rate，hospitalization time，in-hospital mortality and sputum drainage amount were also recorded. Results：When compared with the general group，post-therapy SpO2 and sputum drainage amount in HFNC group was significantly improved；heart rate，respiratory rate，reintubation rate and pharyngalgia/rhinodynia incidence were significantly decreased in HFNC group（P<0.05）. Conclusion：For treating AHRF，HFNC has a better therapeutic effect than the general oxygen therapy，which can significantly improve the oxygenation in AHRF patients after thoracotomy，increase sputum drainage amount and reduce re-intubation rate；after HFNC，patients’ clinical symptoms are significantly improve and patients have a good tolerance. Therefore，HFNC deserves application in the general ward.