The novel implantable stimulus driver for epileptic seizure suppression with low power design and adaptive loading consideration was proposed in this work. The stimulus driver consisted of the output stage, charge pump system, and adaptor can constantly provide 40-μA output stimulus currents, as the electrode impedance varies within 10∼300 kΩ. The performances of this design have been successfully verified in a silicon chip fabricated by a 0.35-μm 3.3-V/24-V CMOS process. The power consumption of this work was only 1.1∼1.4 mW. The proposed stimulus driver has been integrated into closed-loop epileptic seizure monitoring and controlling system for animal test.