The upper portions of sandy beaches usually have a strip of debris deposited by the action of waves and tides known as "drift line" or "stranded wrack". This deposit is inhabited by amphipods Talitridae and insects, particularly beetles of the family Staphylinidae. For their sensitive to environmental variations, these beetles can be considered important bio-indicators of sandy beach ecosystem health. In the southern coast of Brazil three species of the genus Bledius Leach, 1819 were reported: Bledius bonariensis, B. fernandezi and B. hermani. The present work analyses the relationship between sandy beach sedimentological and morphodynamic characteristics and the occurrence pattern of Bledius species from data obtained on a preliminary survey on 12 sandy beaches of Paraná state. B. hermani was the most abundant and frequent species, present in ten of the 12 beaches studied. B. fernandezi showed a positive correlation with morphodynamics and sedimentological characteristics. Furthermore, B. hermani was dominant on beaches with coarse sand and more reflective to intermediate morphodynamic. B. bonariensis showed higher densities at beaches with dissipative characteristics near the mouth of Paranaguá Bay. The highest densities of Bledius were recorded on inhabited Superagüi beaches, located in a national park. This suggests that the group could be affected by human interference, particularly urbanization.