Mate choice is one of the most important aspects of sexual selection, and uncovering the mechanisms behind mate choice is a central issue in sexual selection studies. Females choose high-quality males as mates to obtain direct benefits such as resources, nutrition, and protection, and in doing so they acquire indirect genetic benefits for future generations. Further studies of female mate choice would improve our understanding of sexual selection and evolutionary processes. Song is one of the most important secondary sexual characteristics in birds and can reflect male territory quality and genetic and physiological status. Females can extract information about male quality by assessing their songs, and more complex songs are preferred over simple ones. Birds inhabit a communication network in which individuals can assess the quality of potential mates by visual and auditory observation of their interactions. In addition, individuals being observed may adjust their signaling behavior. Audience effects are defined as changes in signaling behavior of an individual engaged in an interaction due to the presence of an audience consisting of a conspecific witnessing the interaction. To date, studies of sexual selection have mainly focused on the driving factors of mate choice and on female audience effects on female-female competition. In contrast, there is limited knowledge about the effects of bird song on mate choice and about male audience effects on female-female competition. Here, we investigated the effects of male song on female mate choice and the male audience effect on female-female competition in Padda oryzivora. In the first part of the study, we used a two-way choice device and stimulated the female by courtship or other songs of a spouse and other males, and we observed female song preference. In the second part of the study, females were observed under three conditions: (a) in the absence of an audience, (b) in the presence of a familiar male, and (c) in the presence of a mate. Our results showed that female P. oryzivora preferred the spouse's song and preferred courtship songs of other males to the non-courtship song of their mates. The courtship song was more attractive than other songs, and its effects were much stronger in stimulating positive female mate choice. The courtship chirp caused a positive response in the female. Females expended more time and resources, but also benefited more, by selecting higher-quality mates. Female P. oryzivora were more aggressive in the presence than in the absence of a male and were more aggressive in the presence of the mate than in the presence of a familiar male. Females appropriately adjust female-female competition behavior when under the male audience effect; whether this is a result of males choosing mates by observing this competition remains to be examined, as does female-female competition in the wild. These results improve our understanding of the underlying mechanism of mate choice behavior in birds.