Major depression is a common mood disorder which jeopardizes our health; hitherto almost all of available antidepressants (ADs) have the same core mechanisms of action in promoting serotonin or noradrenaline function in the brain.The major limitation of todays ADs is that chronic treatment (3-6 weeks) is required before a therapeutic response is realized.More effective and faster treatments for depression are in urgent demand.Adult neurogenesis (the birth of new neurons) continues postnatal and into adulthood in the brains of multiple species, including humans.Recently numerous findings give rise to the hypothesis that AD effect and increasing adult hippocampal neurogenesis may be causally connected.Multiple classes of ADs increased hippocampal neurogenesis in a chronic but not acute time course, which corresponds to the therapeutic time lag caused by current ADs; whereas ADs would lose their effects in behavioral models of depression when hippocampal neurogenesis was deleted.This review presents the major current approaches to understand adult neurogenesis and the causally connected evidences between AD effects and adult hippocampal neurogenesis, and the potential underlying mechanisms.Finally, we will combine with our recent research progresses, which provide a promising strategy that enhancing adult hippocampal neurogenesis might be a new avenue for the development of novelty ADs.