The present invention provides a small and low running-cost device capable of minimizing the generation of contamination sources as much as possible while performing a series of all the desired manipulations. A device for manipulating a target component in a manipulation tube, comprising: a manipulation tube comprising a tube having an optionally-closeable open end for supplying a sample containing a target component at one end and a closed end at the other end, and a manipulation medium accommodated in the tube and having a gel layer and an aqueous liquid layer multilayered in a longitudinal direction of the tube; magnetic particles that should transport the target component; and magnetic field applying means capable of applying a magnetic field to the manipulation tube to move the magnetic particles in the longitudinal direction of the tube.