Global Navigation Satellite System(GNSS) time transfer techniques with low cost, high precision and wide coverage, are widely used in high precision time-frequency. Traditional satellite common-view (CV) technology uses Common GNSS Generic Time Transfer Standard(CGGTTS) file to realize post high-precision time transfer, and it is difficult to realize real-time time transfer. To meet the needs of digital converter station, power internet of things, mobile communication and etc. This paper studies real-time common-view time transfer based on the pseudo-range observations of the Beidou-3 global navigation and positioning system (BDS-3). Short baseline and Xi’an-Sanya long-baseline real-time CV time transfer experiments are carried out to evaluate the performance of real-time CV method. The results show that the precision of real-time CV time transfer based on BDS-3 is better than 1ns, and it can provide nanosecond time synchronization and nanosecond timing services for time-frequency system, digital converter station and some other applications.