A marine park is a park consisting of an area of sea (or sometimes a lake protected for recreational use. Most marine parks are designated by governments, and organized like watery national parks, but there are also private marine parks. A theme park featuring sea life may be a sort of combination of marine park, public aquarium, and zoo, with a variety of animals kept inside, outside in enclosed tanks, or outside in the sea, fenced in order to keep them from wandering off.

Some marine parks are quite large; the Great Barrier Reef Marine Park in Australia is the largest, at 350,000 sq km.

Although for many uses it is sufficient to designate the boundaries of the marine park and to inform commercial fishing boats and other maritime enterprises, some parks have gone to additional effort to make their wonders accessible to visitors. These can range from glass-bottomed boats, to small submarines, to windowed undersea tubes.

Private marine parks: