Hemorrhagic pericardial effusion (HPE) is a subtype of pericardial effusion marked by the accumulation of serosanguineous or bloody fluid within the pericardial cavity. We present a case of a 65-year-old female who presented to the hospital with abdominal pain and was found to have pericardial effusion. The patient’s condition evolved into cardiac tamponade, and employing diagnostic techniques such as imaging and pericardiocentesis, a substantial bloody effusion was uncovered, indicative of HPE. This report underscores the complexity of HPE diagnosis and examines the non-iatrogenic etiological factors contributing to HPE, focusing on three primary causes: malignancy, infection, and autoimmune disorders. It offers a detailed exploration of each etiology, backed by current medical literature and case studies. It outlines the diagnostic strategies pertinent to each cause, underscoring the need for a tailored approach to manage such cases. It emphasizes the importance of a meticulous and individualized diagnostic process, vital for accurate identification and effective management of this condition.