The Eurasian oystercatcher (Haematopus ostralegus) also known as the common pied oystercatcher, or palaearctic oystercatcher, or (in Europe) just oystercatcher, is a wader in the oystercatcher bird family Haematopodidae. It is the most widespread of the oystercatchers, with three races breeding in western Europe, central Eurasia, Kamchatka, China, and the western coast of Korea. No other oystercatcher occurs within this area. The extinct Canary Islands oystercatcher (Haematopus meadewaldoi), formerly considered a distinct species, may have actually been an isolated subspecies or distinct population of the Eurasian oystercatcher.

This oystercatcher is the national bird of the Faroe Islands.The oystercatcher is one of the largest waders in the region. It is 40–45 cm (16–18 in) long, the bill accounting for 8–9 cm (3.1–3.5 in), and has a wing-span of 80–85 cm (31–33 in). They are obvious and noisy plover-like birds, with black and white plumage, red legs and strong broad red bills used for smashing or prising open molluscs such as mussels or for finding earthworms.

 Despite its name, oysters do not form a large part of its diet. The bird still lives up to its name, as few if any other wading birds are capable of opening oysters at all.

This oystercatcher is unmistakable in flight, with white patches on the wings and tail, otherwise black upperparts, and white underparts. Young birds are more brown, have a white neck collar and a duller bill. The call is a distinctive loud piping.

The bill shape varies; oystercatchers with broad bill tips open molluscs by prising them apart or hammering through the shell, whereas pointed-bill birds dig up worms. Much of this is due to the wear resulting from feeding on the prey. Individual birds specialise in one technique or the other which they learn from their parents