The declining function of the organism in elderly depressed patients makes the use of antidepressant drugs less effective and prone to adverse effects, which limits the use of drugs. Especially for elderly patients with refractory depression whose treatment with multiple antidepressants is ineffective, it is often difficult to select the appropriate antidepressant drug treatment again and not easy to add to the therapeutic dose, which becomes a difficult point of drug treatment. Modern electroconvulsive therapy (MECT) is a safe and effective treatment method based on traditional electroconvulsive (ECT) with soft twitch technique. Since the 1980s until now, there have been some retrospective studies prospective controlled studies at home and abroad initially discussing the efficacy of MECT on depression in the elderly, especially the application of MECT in the acute phase, most of which concluded that MECT is safe, suitable for the elderly, effective for both acute treatment and maintenance treatment of refractory depression, reducing the relapse rate and re-hospitalization rate. MECT has traditionally been used only for the acute treatment of psychiatric disorders. However, maintenance therapy is critical after acute MECT treatment, and Sackeim and his group found in a randomized controlled study that 39% relapsed after 10 weeks of maintenance treatment with lithium carbonate, 60% relapsed after 10 weeks of treatment with nortriptyline, and 84% relapsed with placebo after acute treatment with ECT. Therefore, Stephens et al. and his group did a study of maintenance therapy with MECT and found that 80% of patients had stable disease during maintenance therapy with MECT. Schwartz and his group found that maintenance treatment with MECT reduced rehospitalization rates by 67 percentage points, and Clarke’s group found that after 5 months of maintenance treatment with MECT, the rehospitalization rate was only one-sixth that of the control group. At present, there are few domestic studies on the use of MECT for maintenance treatment of depression. This study confirms that combined MECT maintenance treatment for elderly patients with depression is not only effective in the acute treatment period, but may also be a better method for maintenance treatment.The mechanism of action of MECT is complex and not yet clear. It is generally believed that the mechanism of action of MECT may be multi-pathway, which is a comprehensive and immediate synergistic effect on multiple receptors and subsequently brings about a new relative balance in the central neurotransmitter system, thereby achieving relief of psychiatric symptoms. Most studies have found MECT to be safe and free of serious adverse effects, with the possibility of transient memory impairment in a few patients and transient headaches in very few. There are no absolute contraindications to MECT, and its risk is no higher than that of general anesthesia: it is safer for elderly patients with frailty, combined fractures, cardiovascular and other somatic diseases, and even safer than some drugs. Therefore, as long as we carefully prepare for the treatment, pay attention to reducing the risk of certain diseases to MECT, try to correct the somatic compensatory function, pay attention to the individualization of the dosage of anesthetics, muscle relaxants and other drugs, as well as mastering the time of electricity and stimulation power. In conclusion, MECT is a safe and effective treatment method that deserves to be widely used in the acute and maintenance treatment of elderly patients with refractory schizophrenia.