A soft sphere transfer device, includes: a water tank into which soft spheres are introduced； a transfer rotation member rotatably disposed in the water tank and including a plurality of accommodation grooves formed along a peripheral edge of the transfer rotation member； and an injection device configured to inject a predetermined substance into the soft spheres by piercing a needle into each of the soft spheres transferred to a needle piercing part by rotation of the transfer rotation member, wherein the water tank includes a pair of side walls facing each other in a width direction, and wherein a narrow width portion having a width equal to or smaller than a diameter of the soft spheres is provided on at least one portion in the width direction among portions of the side walls corresponding to the needle piercing part.
