The invention provides a micro-electrochemical processing fuzzy on-line control system based on short-circuit time. The micro-electrochemical processing fuzzy on-line control system comprises a superordinate control system and a subordinate control system; a macro-motion control system is used for controlling a motor to implement a large-stroke motion of the processing; a micro-motion control system is used for controlling a piezoelectric actuator to implement micro feed rate of super-finishing; the superordinate control system is used for sending a processing instruction and processing parameters to the subordinate control system; the subordinate control system implements time division invoking of the control logic and is used for correspondingly driving the macro-motion control system and the micro-motion control system and coordinatively controlling a macro displacement mechanism and a micro displacement mechanism; and finally large-stroke motion for high-precision micro precise regulation and processing of a clearance between processing electrodes in a micro-electrochemical processing process is realized. The micro-electrochemical processing fuzzy on-line control system realizes motion control in a micro-electrochemical processing system by adopting a macro motion control method and a micro motion control method, wherein a servo motor realizes large-stroke micro motion of the processing; and the piezoelectric actuator realizes micro feed displacement and precise positioning of the processing.