A tubo-ovarian abscess (TOA) is a common complication of pelvic inflammatory disease in premenopausal women; however, in virginal females, TOAs are an exceedingly rare occurrence. Within this rare subset of patients, there is almost always an underlying condition, such as vaginal voiding, or a concomitant disease process. A virginal adolescent female with no prior medical history presented with a large pelvic mass which proved to be a TOA. An exploratory laparotomy was eventually required to establish the diagnosis. Open drainage and antibiotic therapy successfully treated the patient. With only the organism, Streptococcus viridians, isolated in her cultures, an etiology of direct ascension from the lower genitourinary tract is implicated. We believe this to be the youngest case of a TOA occurring in a virginal adolescent female without a predisposing condition. A TOA should be considered in the differential diagnosis of pelvic masses in previously healthy pediatric patients regardless of their sexual activity.