For wave energy converters, the sea is an awful running environment, the devices often face extreme wind and waves, electrochemical corrosion, and biofouling factors such as adverse effects, especially corrosion and its own structure fatigue caused by stress damage, which is likely to lead to the breakage of the buoy structure into the water, which affects the operation of devices, and even sink them. Based on the software STAR-CCM+, this study established a process model of internal water intake after the fracture of the buoy of the multi-buoy device. The adverse effects of water intake were evaluated through the response power and pitch motion amplitude of each buoy to explore the survivability and anti-sinking ability of this type of device. According to the results, the first buoy has the least adverse effect on the inflow. However, compared with the normal working condition, the power has also decreased by nearly 50%.