A wild fishery is a natural body of water with a sizeable free-ranging fish or other aquatic animal (crustaceans and molluscs) population that can be harvested for its commercial value. Wild fisheries can be marine (saltwater) or lacustrine/riverine (freshwater), and rely heavily on the carrying capacity of the local aquatic ecosystem.

Wild fisheries are sometimes called capture fisheries. The aquatic life they support is not artificially controlled in any meaningful way and needs to be "captured" or fished. Wild fisheries exist primarily in the oceans, and particularly around coasts and continental shelves, but also exist in lakes and rivers. Issues with wild fisheries are overfishing and pollution. Significant wild fisheries have collapsed or are in danger of collapsing, due to overfishing and pollution. Overall, production from the world's wild fisheries has levelled out, and may be starting to decline.

As a contrast to wild fisheries, farmed fisheries can operate in sheltered coastal waters, in rivers, lakes and ponds, or in enclosed bodies of water such as pools or fish tanks. Farmed fisheries are technological in nature, and revolve around developments in aquaculture. Farmed fisheries are expanding, and Chinese aquaculture in particular is making many advances. Nevertheless, the majority of fish consumed by humans continues to be sourced from wild fisheries. As of the early 21st century, fish is humanity's only significant wild food source.

According to the Food and Agriculture Organization (FAO), the world harvest by commercial fisheries in 2010 consisted of 88.6 million tonnes of aquatic animals captured in wild fisheries, plus another 0.9 million tons of aquatic plants (seaweed etc.). This can be contrasted with 59.9 million tonnes produced in fish farms, plus another 19.0 million tons of aquatic plants harvested in aquaculture.

Worldwide, freshwater lakes have an area of 1.5 million square kilometres. Saline inland seas add another 1.0 million square kilometres. There are 28 freshwater lakes with an area greater than 5,000 square kilometres, totalling 1.18 million square kilometres or 79 percent of the total.

Freshwater fisheries are essential to supporting human life around the globe whether they are used for recreation or commercial use. Climate change presents several challenges in sustaining these fisheries as waters become warmer resulting in decreased dissolved oxygen, as the toxicity of pollutants increases, and as the physiological changes in fishes and changes in their habitat systems alter what we are used to. Deoxygenation and eutrophication are two major effects that are detrimental to fish and ecosystem health and the problem is more prevalent as the size of the body of water decreases. Details on the changes occurring in fish physiology and their habitats can be found at the respective citation.

Increased management and surveillance on freshwater fisheries will be vital to the longevity, sustainability, and productivity of the fisheries and essential to maintaining our food production from that source.

Pollution is the introduction of contaminants into an environment. Wild fisheries flourish in oceans, lakes, and rivers, and the introduction of contaminants is an issue of concern, especially as regards plastics, pesticides, heavy metals, and other industrial and agricultural pollutants which do not disintegrate rapidly in the environment. Land run-off and industrial, agricultural, and domestic waste enter rivers and are discharged into the sea. Pollution from ships is also a problem.