The invention discloses the use of the G-CSF dimer in the preparation of a medicament for the treatment of neurodegenerative diseases. Use of the G-CSF dimer of the present invention can significantly increase the number of dopaminergic neuron in the substantia nigra in PD model animals and enhance the function of dopaminergic neurons. In addition, the G-CSF dimer can significantly reduce apoptosis of neuron in hippocampus and improve learning and memory ability of AD model rats. Serum half-life of the G-CSF dimer of the invention is prolonged and the loss of neurons is effectively prevented, providing a better therapeutic effect in treatment of neurodegenerative disease.
