A particle charging apparatus for charging a photo-sensitive drum by magnetically holding magnetic particles in a charging zone and impressing a charging bias on the magnetic particles. Adjacent to an opposed pole which is disposed on the back side of the photo-sensitive drum on the charging zone upstream side for forming a vertical magnetic field, an opposite polarity magnet or magnetic member is disposed such that a mainly horizontal magnetic field is formed on the drum by the opposed and adjacent poles. A vertical magnetic field is formed on the charging zone downstream side by a main pole and the opposed pole. A non-magnetic sleeve with the main pole therein is rotated in the direction opposite that of the drum, thus causing magnetic particles in the vertical magnetic field to be circulated toward the charging zone upstream side. Leakage and spattering of magnetic particles out of the charging zone is effectively prevented by simple construction, and stable charging is permitted even with a reduced photo-sensitive drum size or with assembling errors of a charging sleeve or the like.