To make it possible to prevent a breakage of a permanent magnet when fixing a field permanent magnet to a yoke.

A linear motor 100 comprises a field 1 and an armature 2 which are facing to each other via a magnetic gap, making the field 1 a stator and making the armature 2 a movable element, wherein the field 1 has: a flat plate-like field yoke 11; a plurality of main pole magnets 14 and interpole magnets 15; a surface 15a at a magnetic gap side of the interpole magnets 15; a surface 15b at a side of two adjacent main pole magnets 14; and a reinforcement member 16 disposed at 15b.