A 61-year-old woman was referred to our hospital due to a liver tumor discovered at a medical checkup. A hypervascular tumor located in liver segment I, measuring 45 mm in diameter, was visualized on ultrasonography. The tumor showed strong uniform enhancement from an early phase on computed tomography and angiography. Right hepatectomy with total caudate lobe resection was performed. Pathological examination revealed the tumor to be a primary leiomyoma of the liver, positive for smooth muscle actin and desmin on immunohistochemical examination. Primary liver leiomyoma is very rare and only 18 cases have been reported to date. The clinical features of these cases from the literature are also discussed.