Subthreshold depression refers to a condition in which individuals have certain depression symptoms without meeting the full criteria for major depression disorder（ MDD）. Although the symptoms of subthreshold depression are not as serious as MDD， the prevalence rate of subthreshold depression among individuals is higher than that of MDD， which seriously affects individuals' mental health and social function. Subthreshold depression is considered as a high risk factor for MDD， but its neuromechanism and intervention is not clear at present. Combined with previous research results， this paper reviews the neuromechanism and intervention of subthreshold depression， analyzes the deficiencies and developmental direction of current studies， in order to provide some reference for future studies.