The present invention relates to an electromagnetically driven valve suited for use in an internal combustion engine and aims at achieving appropriate operating characteristics in accordance with operating conditions of the internal combustion engine at the time of opening or closing a valve body. An armature moving together with the valve body is provided and upper and lower cores are disposed on opposed sides of the armature. The upper core and the lower core accommodate upper and lower coils, respectively. An annular protrusion, formed not on the upper core but on the lower core only, has an inner diameter slightly larger than an outer diameter of the armature.