The fossil assemblage of tube dwelling polychaetes of the families Sabellidae andSerpulidae from the Oxfordian in Hády Quarry is described here in detail for the firsttime in one place. The 9 species belong to 6 genera: GlomerulaBrünnich Nielsen, 1931, Metavermilia? Bush, 1905,SerpulaLinnaeus, 1758, CementulaBrünnich Nielsen, 1931, PropomatocerosWare, 1975, and PlacostegusPhilippi, 1844. Their taxonomy and palaeoecology are discussed. All the serpulidsdescribed here were obligate encrusters, but the sabellid Glomerula canlive on hard and on soft bottom. Relatively rare finds of serpulid tubes attached tobrachiopod valves show their orientation suitable for catching microscopic food rests outof the water current caused by the brachiopods’ lophophorate activity. During the firstphases of... Oxfordian sedimentation, water energy was high at Hády. Bioerosion of polychaetetubes indicates a moderately high water energy in a circa 100 m deep shelf sea.