Five species of Tardigrada were found in two moss samples collected from the Hornsund area (Ariekammen, Spitsbergen) including one new to science. The new species, Isohypsibius karenae sp. n., differs from the other similar congeners mainly by having a different type of cuticular sculpture, a different macroplacoid length sequence, by the presence of lunules and cuticular bars under claws as well as by some morphometric characters. The current study increases the number of Isohypsibius species known from Svalbard to thirteen.