A linear motor coil assembly includes a base plate (1), a line of iron cores affixed longitudinally on the upper surface of the base plate, multiple coils respectively provided for the iron cores, and a first cooling tube being in contact with contacts the multiple coils and through which a first refrigerant passes. The lower surface of the base plate can be attached to a precision table of a machine tool or a semiconductor manufacturing apparatus. A groove (8) that extends longitudinally in linear fashion is formed on the lower surface of the base plate. A second cooling tube (92, 94), through which a second refrigerant passes, provided within the groove is additionally provided in the linear motor coil assembly.