Abstract: OBJECTIVE To explore the diagnosis value analysis of pre-albumin (PA) on COPD and analyze the effect of pathogens causing infections on PA, so as to provide reference for clinical diagnosis and treatment. METHODS A total of 170 cases of patients with COPD combined infection in our hospital from Apr. 2013 to Feb. 2015 were enrolled as infection group. The level change of PA in serum and pathogens distribution were under analysis, and at the same time, 120 cases of healthy subjects were chosen as control group. The clinical indexes from two groups were compared and SPSS 19.0 was used for statistic analysis for data. RESULTS A total of 178 strains of pathogens were isolated from the specimen from the 170 cases of patients, mainly gram-negative bacteria, totally 94 strains, accounting for 52.8%. The PA in serum decreased significantly in infection group, but the interleukin-2 (IL2), IL6 and IL10 increased greatly, and the difference was significant compared with control group (P<0.05). CONCLUSION PA can be taken as a valuable indicator for the diagnosis of CODP and the PA is decreased significantly after infection.