Post-stroke depression (PSD) is one of the most common complications after stroke, with a high prevalence. PSD can affect prognosis and rehabilitation of stroke, increase risks of mortality and suicide, and escalate the economic burden on individuals and society. Studies have shown that transcranial alternating current stimulation (tACS) can also be used to treat depression, insomnia and anxiety. So far, this stimulator has been approved by FDA. However, there have not been any reports on the use of tACS in the treatment of depression and PSD in China. In this trial, the efficacy and safety of the tACS will be assessed with the rigor methodology manner.