As one important kind of renewable energy, solar energy has become a key factor of Chinese renewable energy developing strategy. Research on the characteristic of PV grid-connected system by hardware-in-the-loop simulation could provide convenient experiment condition and accurate result. This paper builds a digital/physical hybrid simulation platform based on RTDS and establishes a 520 kWp PV grid-connected system, in which maximum power point tracking (MPPT) and grid-connected control are achieved. At last, the feasibility and effectiveness of hybrid PV system are validated by the analysis of hardware-in-the-loop result in RTDS.