〔Abstract〕 Objective To investigate the application value of intravenous injection of human immunoglobulin combined with mechanical ventilation in patients with acute lung injury. Methods A total of 60 patients with acute lung injury admitted to the First Affiliated Hospital of Fujian Medical University from January 2020 to December 2020 were selected and divided into control group and observation group according to odd and even admission time, with 30 cases in each group. The control group was treated with mechanical ventilation, and the observation group was treated with intravenous human immunoglobulin combined with mechanical ventilation, and the therapeutic effects of the two groups were compared. Results The total effective rate of observation group was 90.00 %, higher than 66.67 % of control group, the difference was statistically significant (P < 0.05); After treatment, acute physiology and chronic health evaluation Ⅱ (APACHE Ⅱ ) and Murray lung injury score in the observation group were lower than those in the control group, arterial partial pressure of oxygen (PaO2) and oxygenation index were higher than those of the control group, arterial partial pressure of carbon dioxide (PaCO2) was lower than that of the control group. Interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) were lower than those in the control group, and the differences were statistically significant (P < 0.05). The times of mechanical ventilation and hospital stay in the observation group were significantly shorter than those in the control group, and the differences were statistically significant (P < 0.05). Conclusion Intravenous injection of human immunoglobulin combined with mechanical ventilation is more effective in the treatment of acute lung injury patients. It can promote the improvement of lung function and help to improve the inflammation of patients.