PURPOSE: To electrochemically control cell proliferation by determining peak electric voltage specific to cells to be controlled and by applying this potential on the acting electrode in a liquid in which the acting electrode and counter electrode are installed.

CONSTITUTION: An acting electrode 1 and counter electrode 2 are installed in an electrolytic cell housed with a suspension prepared by suspending cells to be controlled in e.g. an aqueous solution containing agar-agar, and a periodical scanning electrode is applied between the electrodes through a potentiostat 5. Then, the peak electric potential value specific to the cells to be controlled is determined based on the resulting (differential) electric current value, and this peak potential or a potential close thereto is applied on the acting electrode.