Toadfish, the common name for a family of marine fishes. There are about 30 species, including several species called midshipmen. Members of the toadfish family range from about 8 to 18 inches (20 to 45 cm) in length. They are dull-colored, usually resembling the rocks and weeds in which they dwell. Toadfish have large, broad heads, and the body tapers to a long, slender tail. Some species have spines that release a mild poison.

A common toadfish along the eastern coast of the United States is the oyster toadfish. It is a shallow-water fish about 10 inches (25 cm) long. Some species of midshipmen have several hundred light-producing organs scattered on their bodies. An example is the 15-inch (38-cm) plainfin, or northern, midshipman, found along the Pacific coast of the United States. It is sometimes called singing fish because of the sounds it makes by vibrating its gas bladder.

Toadfish make up the family Batrachoididae. The oyster toadfish is Opsanus tau; the plainfin midshipman, Porichthys notatus.