In this paper, samples of mosses, lichens and cryptogams (mosses mixed with lichens) collected from Słowiński National Park (northern Poland) were studied for water bears (Tardigrada). In total, 27 tardigrade taxa were identified: 21 to the species level, one identified as „cf.” and three to the genus level, with six species (Eremobiotus ginevrae, Hypsibius dujardini, Hypsibius scabropygus, Milnesium beasleyi, Minibiotus intermedius and Notahypsibius pallidoides) being new records for Poland. Two possibly new for science species were also found, belonging to genera Diphascon and Mesobiotus. Additionally, a very rare eutardigrade Pseudohexapodibius degenerans has been found in the samples analyzed in the present study for the first time outside of the type locality. The effects of habitat and substrate on species richness were also investigated and showed no significant differences between mosses and lichens, as well as all substrates except for concrete walls. Keywords: Europe; sand dunes; tardigrades; new records; xerophilous species; biodiversity.