[Objectives] The Chinese Pangolin Manis pentadactyla, currently an endangered species living in the southern region of the Yangtze River in China, may experience various stress factors after being introduced into artificial captive environments, making it susceptible to immune- or metabolism-related diseases. The case analysis of abnormally deceased pangolins in this study aims to provide reference data for the prevention and treatment of similar diseases, thereby improving the health status of captive pangolins. [Methods] This study focuses on the case of a deceased Chinese Pangolin, analyzing the cause of death through autopsy, microbiological tests on tissues and organs, and histopathological analysis using hematoxylin-eosin (H.E) staining. [Results] The body of pangolin was dissected to observe pathological changes. The lungs exhibited obvious congestion with white spots, while no significant abnormalities were found in other organs. Using the VITEK2 bacterial identification system, Citrobacter freundii was detected in the liver tissue, and Serratia fonticola was found in the lungs (Table 1). Pathological analysis revealed severe necrosis and structural disarray in multiple organs (such as the liver, kidneys, lungs, and intestines), indicating rapid disease progression and severe deterioration (Fig. 1). The death of the Chinese Pangolin was caused by infection with C. freundii, which led to an inflammatory response in the digestive organs, affecting digestive function. There was widespread necrosis of columnar epithelial cells in the intestinal mucosa, resulting in symptoms such as loss of appetite and diarrhea. The prolonged symptoms weakened the pangolins immune system, leading to a respiratory infection by S. fonticola in the lungs, where inflammation was pronounced, and the alveolar cavities were filled with proteinaceous edema fluid. The results of the antibiotic susceptibility test showed that C. freundii is more sensitive to fluoroquinolones and aminoglycosides, while exhibiting resistance to penicillin, tetracyclines, macrolides, and cefazolin. S. fonticola was found to be more sensitive to aminoglycosides and moderately sensitive to fluoroquinolones, but resistant to penicillin, tetracyclines, macrolides, and cefazolin (Table 2). [Discussion] Both C. freundii and S. fonticola are opportunistic pathogens. After entering captivity, Chinese Pangolins are often in a stressed state, leading to weakened immunity and increased susceptibility to these opportunistic infections. The unique physiological structure of pangolins, especially their digestive and respiratory systems, makes them highly sensitive to environmental changes, thus more vulnerable to infections. Improving captive conditions to reduce stress responses, closely monitoring for diseases with early interventions, and selecting and using appropriate antibiotics could effectively reduce the risk of infection and improve the survival rate of pangolins. This study will also provide stronger support for future pangolin conservation efforts.