In nuclear transplantation, especially in enucleation, rotating the oocyte to a certain position has been an important work. Therefore, we developed an oocyte rotation system by using electrostatic force, which is known to be excellent in handling minute objects. This system has become the basic technology for the automated nuclear transplantation system. Mouse oocyles were rotated at a speed of about 60 deg/s by electrostatic phenomena (i.e. electrorotation and dielectrophoresis), and the direction of rotation could be reversed. In order to confirm the electrostatic effect on the fertilization and developmental ability of oocytes, we performed IVF and nuclear transplantation with rotated oocytes. The result was that the fertilization and developmental ability of the rotated oocytes was the same as that of the control, proving that rotation by electrostatic force does not influence the fertilization and development ability of oocytes.