Objective To describe the current situation of hyperoxemia in ICU patients on oxygen therapy, and to provide references for standardization of oxygen therapy. Methods The patients receiving oxygen therapy were selected by convenience sampling method. The incidence rates of hyperoxemia under different ways of oxygen therapy were described. Results A total of 1 007 patients on oxygen therapy were included, of whom, 376 patients (37.34%) had hyperoxemia and 579 patients (57.50%) had SpO2>0.98. The difference in incidence rates of hyperoxemia， SpO2， and outcomes between different ways of oxygen therapy were statistically significant (P<0.05，P<0.01). Compared with patients receiving oxygen therapy via double nasal catheter or mechanical ventilation, patients receiving oxygen therapy via mask or T tube were more likely to have their SpO2>0.98. Conclusion In ICU, the incidence rate of hyperoxemia in patients receiving oxygen therapy is at a high level. In clinical practice, nurses should pay attention to the harm of hyperoxemia, take measures to reduce hyperoxemia induced by oxygen therapy, correct the traditional fallacy regarding oxygen therapy, and provide proper oxygen therapy to patients.