PURPOSE: A composition containing umbilical cord blood-derived stem cells for preventing and treating neurodegenerative diseases is provided to differentiate the stem cell to nerve cells and to suppress inflammation. CONSTITUTION: A composition for preventing or treating neurodegenerative diseases contains umbilical cord blood-derived stem cells. The stem cells is differentiated to nerve cells or myelin cells(MBP-positive). The growth of nerve cells is promoted by ERK1/2, PI3K, AKT, GSK3-beta, JAK2, or STAT3 signal transduction. The composition is formulated by transparent type or intravenous administration. 본 발명은 제대혈 유래 줄기세포를 함유한 신경퇴행성 질환 예방 및 치료용 조성물에 관한 것이다. 본 발명에 의하면, 제대혈 유래 줄기세포는 신경세포로 분화하고, 내인성 신경세포의 생존과 성장을 유도함과 동시에 염증을 억제함으로써 신경퇴행성 질환을 치료할 수 있다.