The hepatoduodenal ligament is a thick anatomical structure wrapped in the peritoneum that constitutes part of the lesser omentum. The hepatoduodenal ligament runs from the porta hepatis to the proximal 2 cm of the duodenum. The hepatic artery proper, common bile duct, and portal vein run through the ligament near its free edge to reach the liver. These three structures are often referred to as the portal triad. The hepatic artery proper is a branch of the common hepatic artery, originating from the celiac trunk. The hepatic portal vein is the main drainage site of the spleen and the small and large intestines. It brings in nutrient-rich but oxygen-poor blood from these organs via the splenic vein, superior mesenteric vein, and inferior mesenteric vein. The common bile duct is a tube-like structure that helps carry bile from the gallbladder to the lumen of the duodenum. It forms from the unification of the cystic duct from the gallbladder and the common hepatic duct. These three important structures exist within the hepatoduodenal ligament. Understanding the location, content, and function of the hepatoduodenal ligament is important when pathology arises or performing surgery in surrounding structures.