Introduction: Brucellosis is one of the most common worldwide zoonotic and still remains endemic in many developing countries including Iran. Splenic abscess is an extremely rare complication of brucellosis. Here we describe the first reported case of splenic abscess due to brucellosis from Iran. Case Presentation: In June 2014, a 17-year-old woman was admitted to the division of infectious diseases at the Imam Khomeini hospital, Ardabil University of Medical Science, Ardabil, Iran, with complaints of fever, nausea, sweating, headache, anorexia, and abdominal pain during the previous 2 months. Abdominal computed tomography (CT) revealed hypodense lesion within the spleen. Serum antibody tested positive at a dilution of 1:1280 by the Standard Tube Agglutination test (SAT), while blood culture yielded negative results. A diagnosis of splenic abscess due to brucellosis was made and started on streptomycin plus doxycycline and rifampin for 6 weeks. Two days after the initiation of the treatment, hemophagocytic syndrome occurred, which was controlled by oral prednisone. She was followed up in the outpatient department and was given further oral antibiotic treatment. After 2 months of treatment, CT results showed complete resolution of splenic abscess. Conclusions: Splenic abscess due to brucellosis should be considered in differential diagnosis of patients who have complaints such as fever, sweating, and abdominal pain. The conservative approach of using antibiotics alone without surgical intervention can be successful in the treatment of splenic abscess due to brucellosis.