The present invention relates to a composition comprising an ischemic serum for promoting the activation of a stem cell, to a method for promoting the activation of a stem cell and to a stem cell, the activation of which is promoted by the composition or the method. The ischemic serum according to the present invention may stimulate the stem cell to facilitate the secretion of a growth factor, improve survival rate, improve mobility to an injured part, improve proliferation rate and maintain characteristics of the stem cell, thus promoting an activation of the stem cell such that the stem cell becomes suitable for transplantation of the stem cell to a patient having a brain injury.
