Although the incidence of purulent pericarditis has decreased significantly in the modern antibiotic era, purulent pericarditis remains a life-threatening disease. Therefore, a high index of clinical suspicion should be maintained to diagnose this life-threatening illness at an early stage. We report an extraordinary case of purulent pericarditis, caused by Klebsiella pneumoniae bacteremia, which developed during the recovery of septic shock with urinary tract infection. Despite of early diagnosis and pericardial drainage, in addition to adequate antibiotics, the patient subsequently developed multiple organ failure leading to death. The case highlights that purulent pericarditis is a rare yet possible disorder complicated from septic shock with bacteremia in the antibiotic era. Therefore, purulent pericarditis should always be considered as a possible complication, especially in patients with K. pneumoniae bacteremia and progressive cardiomegaly.