蛤蜊（汉语拼音：gé lí），又作蛤蛎，也称为蛤、文蛤、西施舌、蚌、花甲，是双壳纲软件动物的统称，其中某些种类可以食用。

蛤蜊是一种对于可食用双瞉贝类的泛称。

在中国古代，蛤、或蚌泛称具两片相等的壳的软件动物，有时特指文蛤。蛤蜊则是指生长在东南沿海中的软件动物。

在福建地区，蛤蜊通常指泥蚶。

在**，可食用的双瞉贝类都被泛称为蛤蜊，如文蛤、花蛤、粉蛤、竹蛤，相当于古代的蚶、车螯和花蛤。居住在海水中的，**称蚶仔（ham-á），主要是指文蛤。居住在淡水中的，**称蜊仔（lâ-á），或蚬，通常是指河蚬。

"Clam" is an informal term used to refer to any molluscans within Class Bivalvia.

Remains first appeared in Cambrian age rocks 510 million years ago. They presently live in both freshwater and marine habitats, and range in adult size from nearly microscopic to the giant clam, which can weigh 200 kg (440 lb). Some have life cycles of only one year, while at least one has been discovered that may be over 500 years old. They lack heads but most can react to changes in light and some, such as the scallops, have rudimentary eyes. Though a common food item, many are too small to be useful as food, and not all species are considered palatable. All clams have two calcareous shells or valves joined near a hinge structure with a flexible ligament, and all are filter feeders.