Objective: To investigate the diagnostic value of peripheral blood neutrophil CD64 index (nCD64IND), monocyte CD14 index (mCD14IND) and interleukin 6 (IL-6) levels in adult pulmonary infection. Methods: A total of 63 adult patients with pulmonary infection hospitalized from December 2020 to February 2021 were selected as the study group and 47 healthy adults as the control group. The levels of nCD64IND, mCD14IND and IL-6 in peripheral blood were determined by flow cytometry. Pearson's method was used to analyze the correlation between the three indices and the common indicators of pulmonary infection, such as CRP and PCT. The ROC curve was drawn to evaluate the sensitivity and specificity of the three indices in the diagnosis of pulmonary infection. Results: The levels of nCD64IND, mCD14IND and IL-6 in peripheral blood of adult patients with pulmonary infection were significantly higher than those of healthy control group (all P＜0.05). Correlation analysis showed that the levels of nCD64IND and IL-6 in peripheral blood of patients were positively correlated with CRP, mCD14IND was negatively correlated with CRP, and the three indices were not significantly correlated with PCT. ROC curve analysis showed that the sensitivity of nCD64IND, mCD14IND and IL-6 levels in the diagnosis of lung infection was 81 %, 58.7 % and 84.1 %, respectively, and the specificity was 89.4 %, 78.7 % and 89.4 %, respectively. Conclusion: The determination of nCD64IND, mCD14IND and IL-6 in peripheral blood has certain diagnostic value for pulmonary infection.