The island of Nåtö, located about 7–8 kilometres south of the town of Mariehamn in the Åland Islands, SW Finland, is probably the most species rich spot regarding indigenous vascular plants in Finland. Studies of the wooded meadows of Nåtö were initiated by Alvar Palmgren in the early 20th century and continued by the author CAH from 1964 onwards with the Nåtö Biological Station as the base. The vascular plant flora of several parts of the Nåtö – Jungfruskär Nature Reserve were studied by both authors from the late 1960s onwards. This paper gives a short description of the Nåtö area and its main vegetation features. The main part is a list of all known observations, information in the literature and voucher specimens in herbaria of the vascular plants of this area.