The present invention relates to a composition for neuronal loss prevention and regeneration and, more specifically, to a composition for neuronal loss prevention and regeneration, containing a telomerase-derived peptide so as to be effective on known diseases caused by neuronal loss and regeneration inability. According to the present invention, the peptide shows preventive and treatment effects on neuronal loss and regeneration inability diseases including Alzheimer's disease, and thus a novel method for treating neuronal loss and regeneration inability diseases can be provided.