During the autumns of 2002-2003 and 2005 the author carried out some fieldwork in the tiny nature reserve “Het Landje van Naber”, south of Hoorn, North-Holland, the Netherlands, in order to make a start with an inventory of its mollusc fauna. So far 31 species could be recorded: 10 terrestrial and 21 freshwater molluscs. The poor representation of prosobranch snails: only two species of Bithynia and one Valvata, is probably due to the low oxygen contents of the water during the summer. The landsnails are most probably under represented and are in need of more attention in the near future.