A liver abscess is an entity that is rarely observed in the emergency department; therefore, it requires timely diagnosis by the clinicians who support this service. The early diagnosis of a liver abscess is challenging as variable and non-specific symptoms are present; furthermore, symptoms may differ in patients with human immunodeficiency virus (HIV) infection. To date, reports on the presentation of diagnostic ultrasound with point-of-care ultrasonography (PoCUS) are limited. The present case report study describes a patient diagnosed with HIV and the presence of a liver abscess confirmed by PoCUS performed in an emergency department. The patient presented with abdominal pain upon palpation in the right hypochondrium and in the thoracoabdominal area, which became more severe with inspiration. PoCUS revealed a hypodense intrahepatic image observed between segments VII and VI, with internal echoes suggestive of a liver abscess. Moreover, it was decided to perform tomography-guided percutaneous drainage of the liver abscess. Antibiotic treatment with ampicillin/sulbactam and IV metronidazole was also commenced. The patient presented clinical improvement and was discharged on the third day.