A linear motor comprising a mover part including; an armature module having an I shaped magnetic iron core and an armature winding of one kind wound on the periphery of the I shaped magnetic iron core through an insulating material. A non-magnetic material holder on which a plurality of armature modules are arranged in a stroke direction is provided. A base upper plate and a base lower plate are provided for attaching the non-magnetic material holder in upper and lower parts respectively. A stator part includes a plurality of field permanent magnets opposed to the I shaped magnetic iron cores through magnetic spaces and field yokes for supporting the field permanent magnets. The non-magnetic material holder has at both end parts thereof through holes for inserting bolts corresponding to the forms and the arranging pitches of the I shaped magnetic iron cores.