The invention discloses a power controlling apparatus for a biochip including M regions. Each region includes a plurality of cells respectively. The power controlling apparatus includes a pulse generating module, a combinational circuit, and M controlling modules. The pulse generating module generates a pulse. The combinational circuit receives the pulse and generates M controlling signals. Each controlling signal has a predetermined phase which is different from the phase of the other controlling signal. The M controlling modules are electrically connected to the combinational circuit. Each of the M controlling signals corresponds to and activates one of the M controlling modules to selectively power on one corresponding region of the M regions. The cells in the corresponding region which is powered have an action potential refractory time that is longer than the power-on interval of the corresponding region.