An electromagnetic interference suppression filter for use with electric circuits including a filter unit comprising a pair of capacitors provided with through holes extending through the axes thereof, respectively, a substantially U-shaped penetration shaft having its two legs fitted through the through holes, respectively, and a ferrite bead mounted on at least one of the two legs of the penetration shaft, the filter unit being mounted on a metal plate by fitting the two legs into holes provided therein, one electrode of each capacitor being conductively connected to the leg, while the other electrode thereof is conductively connected to the metal plate, respectively, the filter unit thus integrated being easily mountable on a printed circuit board or the like thereby resulting in an electromagnetic interference suppression filter of a simplified construction suitable for mass production and having high filter characteristics.