Cheilopogon agoo, commonly known as the Japanese flying fish, is a marine pelagic ray-finned fish in the family Exocoetidae. It is native to the western North Pacific Ocean, particularly around Japan, Korea, Taiwan, and parts of coastal China, inhabiting warm temperate to subtropical surface waters. The genus name Cheilopogon derives from Greek cheilos meaning “lip” and pogon meaning “beard”, referring to morphological features of the mouth region. The species epithet agoo reflects its regional Japanese name, "ago", which either references the fish's physical jaw or its jaw-dropping flavor. Like other flying fish, it is capable of extended glides above the water using enlarged pectoral fins to evade predators.

Historically, Cheilopogon agoo has been an important seasonal coastal fish in Japanese fisheries, especially in western Japan and Kyushu, where it has long been valued both as fresh seafood and for its roe. As a food source, Cheilopogon agoo is consumed fresh, grilled, dried, or processed. In Japan, it is especially associated with the production of ago-dashi, a high-quality soup stock made by simmering dried flying fish, prized for its clean, umami-rich flavor. The fish is typically split, cleaned, and dried before being lightly toasted and infused in water to extract flavor compounds. Fresh specimens may be grilled whole or filleted and served with seasonal accompaniments. The roe is also eaten and may be lightly salted or incorporated into regional dishes. The dried fish form is particularly important as a foundational ingredient in certain regional broths in Nagasaki and other parts of Kyushu.

Compounds present in Cheilopogon agoo include omega-3 fatty acids such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), inosine monophosphate (IMP), taurine, vitamin D (cholecalciferol) and vitamin B12 (cobalamin). IMP is water soluble and readily extracted into broths, contributing significantly to the flavor profile of ago-dashi. As a smaller pelagic fish, Cheilopogon agoo generally accumulates lower levels of methylmercury than large predatory species, making it a comparatively lower-risk marine protein source when harvested from clean waters.