Cap: 8-30 cm across, hemispherical, when young, later plane, smooth surface, cracked if dry, hazelnut-brown, margin thickly rounded, obtuse.
Hymenophore: first white later yellow to olivegreen.
Spore print: olive brown
Spore: fusiform, 13,3-17,1 x 4-5 μm
Stem: 8-20 x 3-8 cm, ventricose to cylindric, later cylindric, white or light brown, covered with a fine white net.
Flesh: whitish, light yellowish under the cuticle, spongy, thick, odor fungoid, taste mild, nutty.
Habitat: in hardwood forests, at beech, oak, chestnut and hornbeam, grows from june till september.
Remarks: similar with Boletus edulis, only Boletus reticulatus grows under oak and more in hardwoods.