Siboglinidae is a family of polychaete annelid worms whose members made up the former phyla Pogonophora and Vestimentifera (the giant tube worms). The family is composed of around 100 species of vermiform creatures which live in thin tubes buried in sediment (Pogonophora) or in tubes attached to hard substratum (Vestimentifera) at ocean depths ranging from 100 to 10,000 m (300 to 32,800 ft). They can also be found in association with hydrothermal vents, methane seeps, sunken plant material, and whale carcasses.

The first specimen was dredged from the waters of Indonesia in 1900. These specimens were given to French zoologist Maurice Caullery, who studied them for nearly 50 years.