Electrostimulation (ES) has long been utilized as a versatile therapeutic strategy for treating human diseases. This talk will first elaborate how the closed-loop ES operates as a close analogue to how the body controls its own functions. The most recent progresses of flexible and complex piezoelectric material innovations in our group will be viewed for implantable nanogenerator development, including 3D printing techniques and degradable piezoelectric biomaterials. In our recent research, we also successfully implemented the closed-loop electrostimulation concept for skin wound healing, hair growth, bone healing and vagus nerve stimulation for obesity control with superb performance. An electrical stimulation bandage was developed that could accelerate skin wounds in rodents. Via a similar design, the electrical pulses were applied to stimulate hair growth and bone healing. In another work, an implanted vagus nerve stimulation system was developedin responsive to the peristalsis of stomach. The electric signals generated by this device stimulates the vagal afferent fibers to reduce food intake and achieve weight control. With the advanced electromechanical material and device design and engineering, the closed-loop electostimulation concept will quickly grow into a very impactful application direction of nanogenerator technology for human wellbeing.