A -glucosidase from Lycoperdon pyriforme, a wild edible mushroom, was characterized biochemically. The enzyme showed a maximum activity at pH 4.0 and 50 degrees C when p-nitrophenyl--D-glucoside was used as a substrate. K-m and V-max values were calculated as 0.81 mM and 1.62 U/mg protein, respectively. The enzyme activity was conserved about 85% over a broad range of pH (3.09.0) at 4 degrees C after 24 h incubation. The activity was fully retained after 60 min incubation at 2040 degrees C. Na+, Li+, Mg2+, Mn2+, Zn2+, Co2+, Ca2+, and Cu2+ did not affect the enzyme activity and 0.25% sodium dodecylsulfate inhibited the enzyme activity approximately 76%. Ethylenediamine tetra-acetic acid, phenylmethanesulfonylfluoride, and dithiothreitol showed no or a little negative effect on the enzyme activity. The resistance of the enzyme to some metal ions, chemicals, and ethanol along with the pH stability, can make it attractive for future applications in industry.