Abstract: Tyrosinase (EC 1.14.18.1) was extracted from potato (Somanum tuberosum) and four edible fungi such as Agaricus bisporus (Ab), Lentinus edodes (Le), Voluariella voluacea (Vv) and Pleurotus eryngii (Pe). The activity, kinetic parameters (Km, Vmax), optimum pH and temperature, activation energy and stability of the enzyme from different sources were determined. Comparatively, tyrosinase from Ab presented the highest activity and stability. The activity order was related to the intrinsic specific activity of the enzyme, the extraction efficiency and the assay conditions.