Objective To investigate the impact of intraoperative red blood cell (RBC) transfusion volume on postoperative oxygenation index in lung transplant recipients. Methods A retrospective analysis was conducted on the clinical data of lung transplant recipients at Wuxi People’s Hospital Affiliated to Nanjing Medical University from 2021 to 2023. Patients were divided into a non-severe primary graft dysfunction (PGD) group and a severe PGD group based on whether their oxygenation index was greater than 200 mm Hg at postoperative 0 h, 24 h, and 48 h. General data and intraoperative RBC transfusion volumes were compared between the two groups to assess their effects on postoperative oxygenation indices at 0 h, 24 h, and 48 h. A binary logistic regression model was constructed to explore the effect values [odds ratios (OR) and their 95% confidence intervals (CI) ] of RBC transfusion volume on oxygenation status at different postoperative time points (0 h, 24 h, 48 h), and the area under the receiver operating characteristic curve (AUC) was calculated to evaluate diagnostic efficacy. Results A total of 351 patients were included, comprising 260 males and 91 females, aged 20 to 77 years. At postoperative 0 h, the OR for intraoperative RBC transfusion was 1.486 (95%CI, P=0.061); at postoperative 24 h, the OR was 3.111 (95%CI, P<0.001); and at postoperative 48 h, the OR was 1.583 (95%CI, P=0.038), indicating that the oxygenation status of lung transplant recipients was significantly affected by the volume of intraoperative transfusion over time. Furthermore, a transfusion volume greater than 975 mL significantly impacted oxygenation at postoperative 24 h and 48 h. Conclusion The volume of intraoperative RBC transfusion has a significant effect on oxygenation status at 24 h and 48 h post-surgery. The amount of RBC transfusion during lung transplantation is associated with the occurrence of severe PGD, and controlling RBC transfusion volume during the procedure may help reduce the incidence of severe PGD.