Video and audio communications between space and ground play an important role in manned space flight. In order to realize video and audio communications between space and ground, an integrated space-ground video and audio communications network is proposed in this paper according to the characteristics of communications link between manned spacecraft and ground station, such as the long delay and the asymmetry of forward and backward link rate. Transmission of video and audio data between space and ground is achieved by IP over CCSDS technology. For different types and priorities of data, a scheduling method combining static priority and polling scheduling strategy is adopted to ensure business transmission requirements. Channel encoding, scrambling, and synchronization words is adopted to ensure the quality of service of video and audio transmission between space and ground. The proposed space-ground video and audio communications network has been verified by both ground test and in-orbit test. The verification results indicate that transmission rate of video and audio communications is uniform, images and sound are clear without jamming, no packet loss is occurred. Thus the proposed network is suitable for the communications between low-orbit manned spacecraft and ground station, and can be used as a reference for manned moon landing and manned Mars landing.