A hatchery is a facility where eggs are hatched under artificial conditions, especially those of fish or poultry. It may be used for ex-situ conservation purposes, i.e. to breed rare or endangered species under controlled conditions; alternatively, it may be for economic reasons (i.e. to enhance food supplies or fishery resources).

Fish hatcheries are used to cultivate and breed a large number of fish in an enclosed environment. Fish farms use hatcheries to cultivate fish to sell for food, or ornamental purposes, eliminating the need to find the fish in the wild and even providing some species outside of their natural season. They raise the fish until they are ready to be eaten or sold to aquarium stores. Other hatcheries release the juvenile fish into a river, lake or the ocean to support commercial, tribal, or recreational fishing or to supplement the natural numbers of threatened or endangered species, a practice known as fish stocking.

Researchers have raised concerns about hatchery fish potentially breeding with wild fish. Hatchery fish may in some cases compete with wild fish. In the United States and Canada, there have been several salmon and steelhead hatchery reform projects intended to reduce the possibility of negative impacts from hatchery programs. Most salmon and steelhead hatcheries are managed better and follow up to date management practices to ensure any risks are minimized.