The invention relates to a current switching battery box selecting and current switching method of a current switching system. The method comprises the steps that firstly, the type of a current switching vehicle battery box is detected; then battery boxes, of the same type as the current switching vehicle battery box, in a current switching station are used as a standby battery box group, the optimal current switching battery box is selected from the standby battery box group according to the charging completion sequence, expected residual lives, total charging amounts and total charging times of the battery boxes, and a current switching battery box cell is selected according to the type of the optimal current switching battery box; and finally the current switching operation is carried out according to the selected current switching battery box and current switching battery cell. The comprehensive assessment is carried out during current switching according to the expected residual lives, total charging amounts and total charging times of the battery boxes, the optimal battery box is selected as the current switching battery box, the goal of comprehensive assessment on the current switching battery boxes is achieved, and thus the problem that the current switching battery boxes cannot be accessed in the prior art is solved.