Environmental noise has long been considered one of the unwelcome aspects of urban life at home. An increasing number of scholars have studied improving indoor acoustic comfort by using the soundscape approach. However, much uncertainty still exists about the relationship between the audio-visual environment and indoor soundscape perception. The current study investigates the interaction effects of traffic sound and window views on indoor soundscape perceptions in residential contexts. Thirty-two participants were presented with 51 scenarios (a combination of 17 window views and three aural stimuli) and requested to assess their soundscape perceptions in a VR experiment. Results showed that traffic noise could moderate the impact of nature, road, and building views on pleasantness, while it can also moderate the effect of water sound and road view on eventfulness. In particular, natural window views were found not to lead to a more pleasant indoor soundscape necessarily; natural window views even decrease the pleasantness of indoor soundscape in the case of heavy traffic noise outside the window. Besides, overall visual indicators, including complexity and openness, have an interactive effect with traffic sound on pleasantness. Last, pleasantness is found to be associated with the appropriateness of indoor soundscape.