Drug delivery systems play a crucial role in the treatment and management of serious medical conditions. Microelectromechanical systems (MEMS) technologies have allowed the development of advanced miniaturized devices for medical and biological applications. However, flexible drug delivery systems (f-DDS) is difficult to achieve due to a brittle natrue of devices. Our group have developed the self-regulated flexible drug delivery system (f-DDS) based on innovativ microelectromechanical systems (MEMS) on plastic substrate. This technology can be integrated with micro-valves, micro-sensors, and CMOS IC-based microcontroller chip to achieve feedback control at a specific time, dosage, and location on curved surface inside human body.