The invention discloses a supercapacitor dynamic charge/discharge control method and device. Dynamic control and adjustment of supercapacitor charging/discharging are achieved by real-time monitoringof a charge state of a supercapacitor bank and voltage and current changes at both ends of a bidirectional DC/DC converter, the charging/discharging efficiency, service life and operational reliability of a supercapacitor energy storage device are improved; on the one hand, according to the charge state of the supercapacitor, dynamic selection of a supercapacitor charging/discharging strategy is achieved, to improve the charge/discharge utilization and usage safety of the supercapacitor; on the other hand, voltage and current feedback control during charging and discharging of the supercapacitor is achieved through the measurement of voltages and currents at both ends of the bi-directional DC/DC converter, and the working reliability of the energy storage device is improved.