The Canary Islands (Spain) are an archipelago of the coast of northwest Africa. Gran Canaria is the third-largest island and located in the centre (Carracedo & Troll, 2016). The island contains a number endemic land snail species (e.g. Brito & Fraga, 2010). Freshwater molluscs are of smaller significance, but are also present. The research of land and freshwater molluscs of the Canaries mainly goes back to the 19th century with the famous works of Webb & Berthelot (1833), Shuttleworth (1852a, 1852b), Mousson (1872), Wollaston (1878), Mabille (1884), Odhner (1931), and others. Recent checklists are available (Groh, 1985; Bank et al., 2002; Brito & Fraga, 2010; Helixebas, 2019) and some more recent papers are cited further in this article. Nevertheless, taxonomic research is still largely based on these old works and many species were never found again since their description or the ecology or proper range is not known. This, together with the threats of global warming (Luque et al., 2013) and the increase of demographic and touristic pressure (Ibáñez et al., 1997) could (and probably already has) detrimental consequences for the survival of these species (see also the assessments on https://www.iucnredlist.org/). Therefore, there is an urgent need for information on ecology, distribution and taxonomy. “Land and freshwater molluscs of Gran Canaria (Spain)” is an occurrence dataset containing 389 observations of 62 different taxa of land and freshwater molluscs encountered on Gran Canaria, an island central in the Canarian archipelago (Spain). Various sites were inspected in a period between 1988 to 2020. The aim is to contribute to the knowledge on the ecology and distribution of these species on the island such that it may aid conservation and research of these organisms in the future. The dataset is published as a standardized Darwin Core Archive and includes for each observation a stable occurrenceID, scientific name, date, and location of the observation, as well as info on lifeStage and organismQuantity, and supplementary remarks on the determination and the observation itself. We have released this dataset to the public domain under a CC0 1.0 Universal (CC0 1.0) Public Domain Dedication (https://creativecommons.org/publicdomain/zero/1.0/).