With the rapid growth of solar energy generation, lightning hazards to photovoltaic (PV) plants have received attention increasingly. Many PV plants are built in the transmission corridor, leading to an increased occurrence of lightning damages. These damages are caused by lightning strikes to the transmission line nearby, which have not been well addressed in the literature. This paper investigates the transient behaviors of a practical PV plant when a nearby transmission line is struck by lightning. Three types of lightning damages are investigated, namely failure of PV inverters, breakdown of bypass diodes, and arcing between metallic parts. Both bypass diode breakdown and arcing-related incidents in the PV systems have not been analyzed systemically in the literature. In this paper, the numerical results of lightning transients are presented. The simulated induced voltage is consistent with the observed result in the practical plant. Several protection measures against lightning to the PV systems are proposed to achieve better protection performance.