[Purpose] The present study examined whether electro-acupuncture therapy reduces post-stroke depression (PSD) and whether motor function impairments interact with the effects of the therapy. [Subjects] Twenty-eight PSD patients were assessed and assigned to either a good or poor motor function group depending on their motor grade. [Methods] The Beck Depression Inventory (BDI), Hamilton Depression Rating Scale (HDRS) and Manual Muscle Test (MMT) were administered at the screening and initial phases of the study, and at the 4th, 8th, 12th and 16th week of the daily electro-acupuncture treatment. [Results] The electro-acupuncture treatment reduced PSD (as assessed by BDI and HDRS) of the patients. In particular, the depression of the good motor function group was significantly more reduced than that of the poor motor function group. The degree of motor function impairment did not change throughout the study in either group. [Conclusion] The results of the present study demonstrate that electro-acupuncture therapy can improve PSD, and that the treatment effect varies depending on the degree of motor function impairment.