We report a checklist of 622 marine molluscs (7 Poliplacophors, 417 Gastropods, 190 Bivalves and 8 Scaphopods) from “El Garraf” coast (Barcelona, NE Iberian Penninsula). From these species, 53 are new findings for the Spanish Mediterranean, and two of them, Trophon barvicensis and Pleurotomella coeloraphe, are reported for the first time for the whole Mediterranean. A new Würm bed associated with a white coral biocenosis has been found off Vallcarca at depths between 250 and 350 m, and is described here. Data about molluscs identified from the gut contents of about 3000 specimens of Astropecten sea stars found between 40 and 350 m depth are also reported. Also, we include comments about some of the listed taxa and a special SEM image collections, particularly of such groups as Cerithiopsidae, deep-sea Turridae, Yoldiidae and Thyasiridae.