Androgen plays an important role in singing of songbirds. Recent studies have shown that androgen levels in vivo not only affect the external morphology of songbirds, but also affect their singing behavior. Androgens (including derivatives) affect singing behavior and singing system in many ways. Based mainly on the results from our research group in the zebra finch, this review summarizes the effects of androgen on singing behavior, excitability and synaptic transmission of projection neurons of singing system, and the interaction of androgen with other neurotransmitter receptors in the brain of songbirds.