Hepatic artery injury is one complication associated with surgery for gastric cancer. This complication does not occur frequently, but it can cause serious problems. Anatomical variations of the hepatic arteries are thought to be a factor in such injuries. Recognizing vascular variations before the operation is thus very important. This report presents a case with a rare variation of the hepatic arteries identified on three-dimensional computed tomography (3D-CT) angiography before gastric cancer surgery. Hepatic artery injury was avoided as a result of the recognition of this extremely rare variation. Preoperative 3D-CT angiography is useful for preventing the complications associated with hepatic artery injury during surgery for gastric cancer.