A fish hook or fishhook, formerly also called angle (from Old English angol and Proto-Germanic *angulaz), is a hook used to catch fish either by piercing and embedding onto the inside of the fish mouth (angling) or, more rarely, by impaling and snagging the external fish body. Fish hooks are normally attached to a line, which tethers the target fish to the angler for retrieval, and are typically dressed with some form of bait or lure that entices the fish to swallow the hook out of its own natural instinct to forage or hunt.

Fish hooks have been employed for millennia by fishermen to catch freshwater and saltwater fish. There is an enormous variety of fish hooks in the world of fishing. Sizes, designs, shapes, and materials are all variable depending on the intended purpose of the hook. Fish hooks are manufactured for a range of purposes from general fishing to extremely limited and specialized applications. Fish hooks are designed to hold various types of artificial, processed, dead or live baits (bait fishing); to act as the foundation for artificial representations of invertebrate prey (e.g. fly fishing); or to be attached to or integrated into other devices that mimic prey (lure fishing). In 2005, the fish hook was chosen by Forbes as one of the Top 20 tools in human history.