Pylephlebitis is defined as an inflamed thrombosis of the portal vein. It is a rare complication of an intra-abdominal infection, and the diagnosis is often missed due to its nonspecific clinical presentation. Symptoms may include abdominal pain, fever, chills, fatigue, nausea, and vomiting. It is important to consider this differential when a patient presents with signs of abdominal sepsis since it has a high mortality rate and is often diagnosed postmortem. Pylephlebitis can be diagnosed via abdominal ultrasound or CT demonstrating a thrombus in the portal vein, and it must be treated early and aggressively with broad-spectrum antibiotics. We are presenting a case of pylephlebitis as well as discussing the diagnosis and treatment of this potentially lethal condition.