Transcranial magnetic stimulation（ TMS） is a widely used noninvasive clinical treatment for depression in psychiatry， neurology and psychology， by regulating the electrophysiological activities of brain nerves. Although it has been reported that transcranial magnetic stimulation has therapeutic effect on depression， its mechanism is still not clear. In this paper， recent researches have been summarized to show the mechanism of TMS on depression from four symptom aspects， including emotional symptoms， cognitive disorders， sleep disorders and appetite disorders.