Rationale: Splenic abscess is rarely discovered during the toddler period. Although most of the cases are typically marked by fever, abdominal pain, and vomiting, some of them may suffer life-threatening situations. This study aimed to explore how early detection can prevent serious disease complications. Patient concerns: A 2-year-old child with persisted fever and shortness of breathing was admitted. Physical examination was decreasing breathing sound on the left side. We gave empirical antibiotics use with chest tube drainage for 2 days in vain. No fever dropping and persistent left upper abdominal pain were noted. A huge mass was found on left spleen incidentally during abdominal ultrasound screen. Diagnosis: Huge splenic abscess. Intervention: High-resolution ultrasound and abdominal computer tomogram were conducted to confirm the diagnosis. Percutaneous drainage under computer tomography-guided with antibiotic use was smoothly. No obvious adverse effects were noted during the treatment course. Rapid clinical improvement with decreasing size was observed by ultrasound 10 days after the treatment and fever subsided. Outcomes: A period of 3-month follow-up revealed no evidence of recurrence of abscess. Lessons: Early diagnosis and intervention are mandatory for splenic abscess to prevent possible ominous consequences. The case study has shown that computer tomography-guided percutaneous drainage, along with appropriate antibiotic therapy, can significantly impact solitary unilocular splenic abscesses, even if they are large. This approach demonstrates the potential to effectively manage splenic abscesses and avoid the need for more invasive procedures such as splenectomy.