Objective To explore clinical characteristics of patients with acquired immunodeficiency syndrome(AIDS) combined with Pneumocystis jiroveci pneumonia (PJP), so as to improve the understanding on standardized diagnosis and treatment of PJP. Methods Clinical data of 101 AIDS patients combined with PJP who were admitted to Butuo People's Hospital of Liangshan Prefecture from June 2016 to June 2019 were analyzed retrospectively, including medical history, symptoms, signs, chest imaging, laboratory examination, treatment and outcome. Results Among 101 AIDS patients combined with PJP, 78.2% (n=79) were young and middle-aged men, 72.3% (n=73) of HIV infection was mainly transmitted by sexual contact. The common clinical manifestations were progressive dyspnea (n=69), fever (n=17), cough (n=15) and so on. Arterial blood gas analysis indicated that patients had hypoxemia (PaO₂<60 mmHg) and significant elevation of lactate dehydrogenase (LDH) in peripheral blood (527.4±85.7)U/L. Combination of other pulmonary infection (bacteria or tuberculosis) were common (n=34). CD4⁺T lymphocyte count decreased significantly (< 200/μL, n=90), and cellular immune function was seriously damaged. The main manifestations of chest CT were multiple ground-glass opacity in both lungs, and diffuse reticular nodular interstitial infiltration from the hilus of lung. Conclusion Clinical manifestations of AIDS patients combined with PJP are various, respiratory system damage is most common, early diagnosis and standardized treatment are the key to the influence of prognosis of AIDS patients combined with PJP.