Abstract: The present invention provides a damaged part treatment composition for repairing a damaged part of a target tissue that includes a stem cell-conditioned medium obtained by culturing stem cells; a damaged part treatment method for repairing or restoring a damaged part of a target tissue that includes administering the damaged part treatment composition to a patient having the target tissue for the damaged part treatment composition in an amount therapeutically effective for repairing the damaged part of the target tissue; a method of treating cerebral infarction that includes administering the damaged part treatment composition to a cerebral infarct patient in an amount effective for repairing a damaged part of the brain; and a method of treating a CNS disease that includes administering, as a CNS disease treatment composition, the damaged part treatment composition to a CNS disease patient in a therapeutically effective amount.