Objective: To investigate the relationship between serum autocrine motor factor (Autotaxin) level and pulmonary ultrasound score (LUS) and the disease severity and 28-day mortality of patients with acute respiratory distress syndrome (ARDS). Methods: Totally 142 ARDS patients admitted to Danzhou People's Hospital from January 2019 to December 2021 were selected, and serum Autotaxin level and LUS score of ARDS patients on the day of onset were detected. According to the survival within 28 days after entering the intensive care unit, ARDS patients were divided into survival group (86 cases) and death group (56 cases). According to the oxygenation index, ARDS patients were divided into mild group (200 mmHg<oxygenation index≤300 mmHg, 36 cases), moderate group (100 mmHg<oxygenation index≤200 mmHg, 61 cases) and severe group (oxygenation index≤100 mmHg, 45 cases). The receiver operating characteristic curve (ROC) was performed to analyze the value of serum autotaxin level and LUS score to predict the death of patients with ARDS. Kaplan-Meier method was used to draw the survival curve, and Log-rank test was used for comparison between groups. Cox multivariate regression analysis was used to analyze the risk factors of death in patients with ARDS. Results: The LUS score [(26.50±5.20 vs 13.45±3.70, t=11.974,P<0.01] and serum Autotaxin level [(54.83±16.28)μg/L vs (32.70±11.85) μg/L,t=13.842,P<0.01] in the death group were significantly higher than those in the survival group, the difference is statistically significant. The serum autotaxin level and LUS score in severe group were significantly higher than those in mild group and moderate group (all were P<0.001). ROC curve showed that the combino ation of autotaxin and LUS score had the largest AUC to predict the AUC of death in patients with ARDS (0.904, 95CI:0.847-0.962), with the highest accuracy of 88.2%. Survival curve analysis showed that the survival rate of high autotaxin group was significantly lower than that of low autotaxin group (44.1% vs 75.7%,P<0.001), and the survival rate of high LUS score group was significantly lower than that of low LUS score group (49.4% vs 73.8%,P=0.003). Cox multivariate regression analysis showed that elevated LUS score (HR=1.983, 95%CI: 1.402-4.715,P<0.001) and Autotaxin level (HR=2.604, 95%CI: 1.853-6.317,P<0.001) were risk factors for death in patients with ARDS (P<0.05). Conclusion: The increase of serum autotaxin level and LUS score is related to the severity and death of patients with ARDS, which are risk factors for 28-day death in ARDS patients, and can be used as a reference mdicator to predict death in ARDS patients.