Behçet's disease (BD) is often associated with neutrophilic dermatosis. However, BD is rarely associated with aseptic abscesses in the spleen or liver. A 2-year-old girl presented to our hospital with a 2-week history of fever, abdominal pain, and a skin ulcer on her leg. Each time her skin was punctured with a needle for a blood test or spinal fluid test, she developed intractable aseptic abscesses on her skin. She was diagnosed with intestinal BD based on gastrointestinal endoscopy findings and was treated with prednisolone, mesalazine, and elemental diet therapy. Although these were effective for her colon ulcers, low-grade fever and mild abdominal pain persisted. Abdominal computed tomography revealed a low-density area in the spleen. Although it is recommended to check the contents with puncture drainage, it was difficult due to the risk of bleeding and pathergy. The abscess expanded despite antimicrobial therapy. We discontinued antimicrobial therapy and switched to intensified immunosuppressive therapy for BD [intravenous infliximab (IFX)]. After administration of IFX, the splenic abscess gradually disappeared, and all her symptoms improved. In cases of BD with splenic abscesses resistant to antimicrobial therapy, intensifying immunosuppressive therapy can be expected to shrink the abscesses and avoid splenectomy.