The release of metals into soil has led to their important accumulation in biota and often alters biological systems. By their ability to secrete enzymes and adapt their metabolism to various sources of nutriment, fungi are key colonizers in terrestrial ecosystems. They play a major role in the biogeochemical cycles and soil functioning. Since fungi represent one of the largest biomass in soils, the response of their extracellular functional systems to metals offers promising perspectives for ecotoxicological assessment. However, the functional diversity of fungi and the metal effect on their functional systems are not well known, limiting the predictive interest of such fungal biomarkers.