Pyogenic liver abscess (PLA) is an uncommon condition, which requires early diagnosis and treatment, due to high mortality, morbidity if left untreated. The incidence rate 3.6 per 100.000 populations with overall mortality 0.2 per 100.000 populations in the United States. Predisposing factors for PLA development were immune deficiency, parasitic invasion, genetic disorders (Papillon-Leferve syndrome, Chronic Granulomatous Disease), abdominal infection [4] and abdominal trauma. The most common cultured bacteria in the last population group were Streptococcus species 29.5%, E.coli 18.1% and 16.3% polymicrobial. Here we report a case of PLA secondary due to Fusobacterium nucleatum in an otherwise healthy adolescent male with no definitive source of infection (cryptogenic). PLA is very rare and to date there is no case reports published with Fusobacterium nucleatum being the causative pathogen in pediatrics (only 13 adult cases have been reported).