Objective To investigate the influencing factors for prognosis in non-severe (mild to moderate) pulmonary acute respiratory distress syndrome (ARDS) patients, and evaluate the efficacy of the risk factors to predict the prognosis. Methods The data of 123 patients with non-severe pulmonary ARDS, hospitalized in the Department of Respiratory and Critical Care Medicine of Beijing Chaoyang Hospital (West Campus) from January 2017 to June 2021, were retrospectively enrolled, and divided into two groups according to 30-day survival condition, i.e., non-survivor group (n=45) and survivor group (n=78). Baseline characteristics, complications, arterial blood gas, blood routine, and levels of fibrinogen, C-reactive protein (CRP), procalcitonin,albumin and brain natriuretic peptide (BNP) were compared between the two groups. Kaplan-Meier and Cox survival analysis were adopted to analyze the risk factors which could affect the survival situation of patients with non-severe pulmonary ARDS.ROC curves were used to assess the efficacy of the risk factors to predict prognosis. Results Compared with survivor group, the proportion of patients with renal insufficiency, deep venous thrombosis and shock, APACHE Ⅱ score, body temperature, respiratory rate, neutrophil to lymphocyte ratio (NLR), fibrinogen and CRP levels in non-survivor group increased, and arterial partial pressure of carbon dioxide (PaCO₂), platelet count and albumin levels decreased (P<0.05). Kaplan-Meier survival analysis showed that kidney failure, deep venous thrombosis and shock were the risk factors of 30-day death in patients with non-severe pulmonary ARDS (P<0.05). Univariate Cox analysis demonstrated that heart rate, temperature, respiratory rate, PaCO₂, NLR, WBC, platelet count, fibrinogen, CRP, albumin and APACHE Ⅱ score were the risk factors of 30-day death in patients with non-severe pulmonary ARDS (P<0.05). Multivariate Cox analysis showed that higher APACHE Ⅱ score (HR=1.094, 95%CI 1.009-1.120, P=0.031), higher NLR (HR=1.087, 95%CI 1.012-1.167, P=0.021) and the presence of shock presented during course (HR=3.135, 95%CI 1.315-6.964, P=0.010) were independent risk factors for 30-day death of patients with non-severe pulmonary ARDS. The cut-off value of APACHE Ⅱ score and NLR in predicting mortality were 16.5 and 8.13, and the area under the curve (AUC) were 0.803 (95%CI 0.727-0.879) and 0.772 (95%CI 0.688-0.856), respectively. Conclusions APACHE Ⅱ score >16.5, NLR >8.13 and presence of shock were the independent risk factors of mortality for patients with non-severe pulmonary ARDS, and these factors could effectively predict prognosis.