〔Abstract〕 Objective To investigate the effect of neutrophil/lymphocyte(NLR), platelet/lymphocyte(PLR), monocyte/lymphocyte(MLR) and C-reactive protein/albumin(CAR) on the prognosis of patients with idiopathic inflammatory myopathy associated interstitial pneumonia(IIM-ILD). Methods A total of 117 patients with IIM-ILD were selected. The clinical and laboratory characteristics in survivors and non-survivors were compared. The NLR, MLR, PLR and CAR optimal cut-off values of the predicted survival rate were calculated by using the receiver operating characteristic curves(ROC). Cox proportional hazard model was used for multivariate analysis to determine the factors affecting prognosis. Results Among 117 patients with IIM-ILD, 37 patients(31.62%) died during the follow-up period. Multivariate analysis suggested that age, high-dose glucocorticoid, hypoproteinemia, anti MDA5 antibody positive and high MLR(>0.599) were independent predictors of poor prognosis in patients with IIM-ILD. Conclusion High MLR can be used to assess the prognosis of the IIM-ILD patients together with other indicators, which may have the value of evaluating the prognosis of IIM-ILD patients.