Depression is a highly recurrent disorder and the full course of treatment is now advocated. The whole treatment of depression is divided into three phases: acute treatment, consolidation treatment and maintenance treatment. 1.Acute treatment Control the symptoms and try to achieve clinical cure. When treating, medication usually starts to work in 2 to 4 weeks. If the patient is not effective with drug treatment for 6-8 weeks, it may be effective to switch to other drugs with different mechanisms of action. 2.Consolidation period treatment At least 4 to 6 months, during which the patient’s condition is unstable and the risk of reignition is high. 3.Maintenance treatment (1) Depression is a highly recurrent disease. 50% to 85% of single-episode depression will have a second episode, and long-term follow-up reveals that the relapse rate is 13% for those with complete remission and 34% for those with partial remission, so maintenance treatment is often needed to prevent relapse. (2) After the maintenance treatment is completed and the disease is stable, the drug can be slowly reduced until the termination of treatment, but the early signs of relapse should be closely monitored and the original treatment should be resumed quickly once the early signs of relapse are detected. (3) There are different opinions on the duration of maintenance therapy, but WHO recommends that only one attack (single attack) with mild symptoms and a long interval (≥5 years) should be treated. Generally, maintenance treatment is not recommended. The majority opinion is that maintenance treatment for the first depressive episode should be 6-8 months; those who have more than two relapses, especially those who have two relapses in the last 5 years, should be maintained. (4) Goodwin and Jamison suggest that maintenance treatment should be considered for patients with adolescent onset, with psychotic symptoms, severe illness, high risk of suicide, and a genetic family history. The duration of maintenance has not been adequately studied, with a general preference for at least 2 to 3 years, and long-term maintenance therapy is advocated for multiple relapses. (5) Some data suggest that the acute treatment dose as the maintenance treatment dose can be more effective in preventing relapse. (6) The new generation of antidepressants has fewer adverse effects, is well tolerated, and is easy to take, which provides convenience for maintenance treatment. If maintenance therapy is to be discontinued, the dose should be reduced slowly (several weeks) in order to observe for signs of relapse and also to reduce withdrawal syndrome.