To resolve the problems of ink drop tailing, satellite drop, and ink ribbon of piezoelectric ink-jet printing, a fluid dynamic modeling method and an adaptive ink-supply method are proposed. First, based on the volume of fluid method, a fluid dynamic model for the jetting and forming of ink drop is set up. According to this model, the numerical analysis for the states of forming, fracture, and flight of ink drops is performed; referring to different boundary conditions of piezoelectric ink-jet process, the inherent relations between ink characteristics and ink drop motion are analyzed, and an optimal viscosity range for piezoelectric nozzle is confirmed. Then, a fuzzy proportional-integral-derivative-based ink-supply control method is developed to achieve the fast and smooth responses for ink temperature and to obtain the required ink characteristics and ink-supply effects. Finally, a microcontroller-based piezoelectric ink-jetting experiment platform is established, and the experiment results show that the fluid dynamic modeling method can simulate the flow field profiles of piezoelectric ink-jet; the fuzzy proportional-integral-derivative-based ink-supply system can improve the printing quality; the print stripes are decreased obviously, and the softer and cleaner images can be obtained.