Klebsiella pneumoniae (KPn) is a gram-negative bacterium, which is an opportunistic pathogen commonly found in the natural environment, and the infection rate of Klebsiella pneumoniae is increased in patients with underlying diseases such as diabetes mellitus, malignant tumors, liver and gallbladder diseases, and those who have received glucocorticoid therapy for a long period of time [1]-[4], which can cause urinary, respiratory, digestive, hematological, neurological and other multi-system infections with high morbidity and mortality rates [5]. Klebsiella pneumoniae infection involving the heart leading to purulent pericardial effusion has a lower incidence, and the literature in this regard reported extremely rare [6], mostly secondary to other parts of the infection, once suspected of pericardial abscess should be immediately performed pericardiocentesis to drain adequately, the application of saline to flush the pericardial cavity, can be thrombolysis of pericardial cavity with antibiotics or urokinase to speed up the process of treatment, to avoid the formation of constrictive pericarditis [7]-[9]. In order to improve clinicians' understanding of this disease, this article reports the diagnosis and treatment of a case of pericardial abscess caused by Klebsiella pneumoniae, with the aim of providing more case references for the clinic.