This study aims to investigate the predictive value of platelet distribution width (PDW) in patients with influenza A virus (IAV) infection. The clinical data of 105 IAV-infected patients was collected and analyzed. We found that creatine kinase (CK), Acute Physiology and Chronic Health Evaluation (APACHE) II score, PDW, and red blood cell distribution width (RDW) were independent risk factors for acute respiratory distress syndrome (ARDS) development. PDW was more effective in predicting ARDS development than CK and RDW, and comparable to APACHE II score. Among ARDS patients, PDW showed a positive correlation with duration of invasive ventilation, APACHE II score, and Sequential Organ Failure Assessment (SOFA) score, and a negative correlation with the arterial pressure of oxygen/inspiratory fraction of oxygen (PaO