A method for determining the shortest weighting path of black start comprises the steps as follows: acquiring charge time, charge power and high-voltage electric reactor capacity of each branch circuit, reducing the charge time, the charge power and the electric reactor capacity of each branch circuit to a preset voltage class standard and a preset power standard, determining the per unit value of charge power and the per unit value of the high-voltage electric reactor capacity of each branch circuit, determining the weighting of each branch circuit according to the charge time, the per unit value of the charge power and the per unit value of the high-voltage electric reactor capacity, and determining the shortest weighting path according to the weight of each branch circuit. The invention provides a corresponding device for determining the shortest weighting path of black start. According to the method and the device provided by the invention, the charge time, the per unit value of the charge power and the per unit value of the high-voltage electric reactor capacity are comprehensively taken into consideration to reasonably determine the shortest weighting path, so as to implement smooth black start.