The European pine marten (Martes martes), known most commonly as the pine marten in Anglophone Europe, and less commonly also known as pineten, baum marten, or sweet marten, is an animal native to Northern Europe belonging to the mustelid family, which also includes mink, otter, badger, wolverine and weasel. It is about the size of a domestic cat. Its body is up to 53 cm in length (21 inches), and its bushy tail can be 25 cm (10 inches). Males are slightly larger than females; on average a marten weighs around 1.5 kg (3.5 lb). Their fur is usually light to dark brown and grows longer and silkier during the winter months. They have a cream to yellow coloured "bib" marking on their throats.

Their habitats are usually well-wooded areas. European pine martens usually make their own dens in hollow trees or scrub-covered fields. Martens are the only mustelids with semi-retractable claws. This enables them to lead more arboreal lifestyles, such as climbing or running on tree branches, although they are also relatively quick runners on the ground. They are mainly active at night and dusk. They have small rounded, highly sensitive ears and sharp teeth for eating small mammals, birds, insects, frogs, and carrion. They have also been known to eat berries, bird's eggs, meat, nuts and honey. European pine martens are territorial animals that mark their range by depositing faeces (called 'scats') in prominent locations.