The mercury content of various parts of single fruit-bodies of the Yellow Bolete Boletus edulis (n = 26), the Field-Mushroom Agaricus campester (n = 23) and of Agaricus silvicola (n = 17) was determined by flameless atomic absorption spectroscopy. In each species the lowest mercury content was found in the stem (x = 1,96--3,21 mg/kg dry wt.), whereas the caps contained significantly more mercury (x = 4,19--6,97 mg/kg dry wt.). The highest mercury content was found in the gills and tubes (x = 4,85--8,77 mg/kg dry wt.), which contained significantly more mercury then the flesh of the caps (x = 3,11--5,60 mg/kg dry wt.). Young mushrooms seemed to contain more mercury then older ones.