The present invention provides a method for controlling the proliferation and differentiation of cord blood-derived hematopoietic stem cells with excellent safety when proliferating them by culturing. The hematopoietic stem cells are inoculated into a medium containing a sonicated liquid component of cord blood. The proliferation and differentiation of the cord blood hematopoietic stem cells can be inhibited in the presence of the sonicated liquid component of cord blood. On the contrary, the proliferation of cord blood hematopoietic stem cells can be accelerated by inoculating the hematopoietic stem cells into a medium containing a non-sonicated liquid component of cord blood. Thus, according to the present invention, by using serum derived from cord blood, it is possible to regulate the inhibition of the proliferation and differentiation of cord blood hematopoietic stem cells and the acceleration of the proliferation of the same as desired.
