We demonstrated that 1) both oxytocin level and SN oxytocin receptor expression are significantly disturbed in the MPTP‐induced PD model; 2) modulating brain oxytocin level or SN oxytocin receptor expression bi‐directionally changes the vulnerability of nigrostriatal DA neurons in the MPTP‐induced PD model; 3) oxytocin may protect nigrostriatal DA signal by reducing DA neuronal excitotoxicity via oxytocin receptors expressed in SN GABA neurons and GABA(B) receptors expressed in SNc DA neuron‐targeted glutamatergic terminals. The gene discussed is OXT; the disease is Parkinson disease.