Abstract: The present application provides a method for preparing mesenchymal stem cell-derived exosomes, the method including: obtaining a cell sample from mesenchymal stem cells and sub-culturing the cell sample, culturing the sub-cultured cells in a substrate medium containing a protein synthesis inhibitory enzyme, and then obtaining a cell culture solution, and isolating exosomes from the cell culture solution, and a cell culture solution produced therefrom. The method for preparing exosomes of the present application has an advantage in that high purity and high concentration exosomes can be isolated.