A cell separating apparatus that can easily separate target cells contained in a fluid is provided. Target cells and a fluid are injected through a storage hole, and ejected to the outside of a rotation disk under the influence of a centrifugal force of the rotation disk. An electric field is applied to the outside of the rotation disk, and the target cells are gathered at a different position from the fluid due to di-electrophoresis. In addition, pivot arms placed at an outer surface of the rotation disk are open, and the open pivot arms collect the target cells. The collected target cell flow in a different storage portion through a fluid flow path. As a result, the target cells can be easily separated.