PURPOSE: To improve an efficiency and reliability of an electromagnetic pump, by making the effective sinking of the heat generated in its stator coil possible.

CONSTITUTION: In an electromagnetic pump, a double duct comprising an outside duct 3 and an inside duct 4 between which a passage 5 is formed to make a conductive fluid 2 flow, a plurality of laminar core blocks 7 provided on the outer periphery of the double duct, and a stator coil 9 wound around the slots of the laminar core blocks 7 by which a progressive magnetic field is generated in the passage 5 filled with the conductive fluid 2, are provided. In the electromagnetic pump, the double duct is formed in the shape of a cylinder, and the shapes of the inner surfaces of the laminar core blocks 7 are so formed that their curvatures coincide with the curvature of the outer peripheral surface of the double duct, respectively.