A 12-year-old female patient was admitted to this hospital on March 19, 2015, because of lower abdominal pain lasting longer than one month. She had an appendectomy in a local hospital two months before admission. Two weeks after this operation, she began experiencing intermittent idiopathic pain in the lower abdomen, which progressively worsened. After admission, the physical examination, B-ultrasound, and enhanced CT revealed several lumpy shadows of mixed density in the pelvic and celiac areas, with a maximum lesion of 14.7×10.5 cm and unclear borders. The concentration of carbohydrate antigen 125 (CA-125) was significantly elevated. Surgery and rapid pathology confirmed the diagnosis of a left ovarian malignant tumor, and routine pathology further indicated ovarian Burkitt lymphoma.