The quince (/ˈkwɪns/; Cydonia oblonga) is the sole member of the genus Cydonia in the family Rosaceae (which also contains apples and pears, among other fruits). It is a small deciduous tree that bears a pome fruit, similar in appearance to a pear, and bright golden-yellow when mature. Throughout history the cooked fruit has been used as food, but the tree is also grown for its attractive pale pink blossoms and other ornamental qualities.

The tree grows 5 to 8 metres (16 to 26 ft) high and 4 to 6 metres (13 to 20 ft) wide. The fruit is 7 to 12 centimetres (2.8 to 4.7 in) long and 6 to 9 centimetres (2.4 to 3.5 in) across.

It is native to rocky slopes and woodland margins in South-west Asia, Turkey and Iran although it can be grown successfully at latitudes as far north as Scotland. It should not be confused with its relatives, the Chinese quince, Pseudocydonia sinensis, or the flowering quinces of genus Chaenomeles, either of which are sometimes used as culinary substitutes.

The immature fruit is green with dense grey-white pubescence, most of which rubs off before maturity in late autumn when the fruit changes colour to yellow with hard, strongly perfumed flesh. The leaves are alternately arranged, simple, 6–11 cm (2–4 in) long, with an entire margin and densely pubescent with fine white hairs. The flowers, produced in spring after the leaves, are white or pink, 5 cm (2 in) across, with five petals.