A seven-year-old boy with cystic fibrosis (CS) who presented with abdominal pain is reported. Ultrasonographic and computed tomographic studies of the upper abdomen revealed unusual liver findings. An ultrasound scan showed a liver that was exceedingly heterogeneous and a mixed echo pattern with dominant hyperechogenicity. Computed tomography showed large, multiple hypodense cyst-like lesions in the liver. Using the ultrasound scan as a guide, a needle biopsy was performed. The pathological findings were in accord with the findings obtained from ultrasonography and computed tomography, and were consistent with pathological findings seen in CS cases.