We investigated vertical migration distances of Vertigo moulinsiana (Dupuy) in conditions of (1) 24-hour illumination and (2) 24-hour darkness. The experiments were carried out in the laboratory, at high and constant humidity (RH 100%), and 22 °C temperature. The snails were placed singly in 150 cm long, vertically oriented transparent plastic tubes (inner diameter: 8 mm). The tubes for the dark experimental variant were covered with aluminum foil, while those for the light variant were evenly illuminated with cold light lamps. A One-Way ANOVA showed that the snails from the 24 h light variant climbed up higher than those kept in the darkness, regardless on the age group.