A fluid dispenser dispenses a fluid alternately from one of a pair of ports (29,31) that are provided on opposite ends of a syringe (26) by moving a piston (42) back and forth inside the syringe. A pair of stirrers (47,48) are provided in the syringe on opposite axial sides of the piston. The stirrers may each individually rotate on an axis that extends in parallel with the moving direction of the piston. A pair of stirrer driving rings (49,50) are mounted on an outer periphery of the syringe in correspondence with the stirrers. Magnets (55,56,59,60) are embedded in the stirrers and the stirrer driving rings such that the stirrer is rotated by magnetic fields that are generated from the stirrer driving ring, as the stirrer driving ring is rotated by a motor (51,52).