Marine ecosystems in active volcanic areas are regularly subject to natural hazards such as being covered by incandescent lava flows, acoustic phenomena caused by microseisms, temporary changes in physicochemical conditions of water bodies and exceptional elevations of temperature. The Piton de la Fournaise (Reunion Island) is one of the most active effusive volcanoes in the world with 27 eruptions between 1998 and 2007 and a mean frequency, over a century, of an eruptive phase every 9 months. It provides a natural laboratory to study the colonization of a blank substrate. Therefore, a project called BIOLAVE was launched in 2010 in order to study species and habitat diversity on the coastal marine area of the volcano, including the first taxonomic inventory for the southeast side of the Island [1]. One hundred fungal isolates were obtained from 1977 lava flow (-25m depth), 2004 lava flow (-70m) and free water (-70m) as preliminary sampling. Density of propagules was as follows: 0.085/g free water (-70m), 20/g 2004 lava (–70m) and 80/g 1977 lava (-25m) (MEA, PDA and Sabouraud media). These isolates should now be identified using phenotypic characteristics and molecular biology.