An objective lens driving device of a sliding shaft type is mounted on an optical information recording and reproducing apparatus. The objective lens driving device includes an armature unit having a magnet magnetized in a plurality of pairs of magnetic poles, and a stator unit having a yoke, and control coils mounted on the yoke. The magnet is disposed with the boundaries between the magnetic poles which are respectively opposite gaps formed in the yoke. The objective lens driving device has an improved reliability and a reduced number of component parts.