The invention discloses an electric power supporting method taking adjacent systems into consideration, and relates to the field of recovery and control of an electric power system. The method comprises the following steps: a, establishing an object function; b, contracting a node; c, calculating a line betweenness; and d, optimizing and recovering a line. According to the invention, through recovering a generator and a load as much as possible and searching for an optimal power delivery path, the network reconstruction process is accelerated, and the path recovery time is shortened. Besides, path recovery and power support of adjacent electric power systems in the condition of a climate disaster are taken into consideration, and black-start recovery after an electric power system fails completely is safer and more reliable.