The invention provides a vehicle brake energy regeneration control method and system; the system comprises a hydraulic energy accumulator, a variable pump/motor, an electromagnetic clutch, a brake pedal switch, an acceleration pedal switch, a gear switch, a road slope sensor, a speed sensor, a pressure sensor of the energy accumulator, a hydraulic control unit and an electric control unit; the system automatically identifies the acceleration or brake intention of a driver, automatically detects the running state of the vehicle and the road slope situation, calculates the control current I1 of the proportional electric magnet of the variable pump/motor on different downgrade road slopes or horizontal roads and at different speeds by adopting the formula (I), calculates the control current I2 of the proportional electric magnet of the variable pump/motor on different upgrade road slopes or horizontal roads and at different speeds by adopting the formula (II) and carries out brake energy releasing circulation control, so as to control the running stability of the vehicle and improve the recovery rate as well as the regeneration rate of the brake energy.