In general, the equipment and lines used in offshore wind farms are different from those of onshore wind farms. Therefore, it is necessary to study the configuration of relay protection for offshore wind farms. This paper analyzes the short circuit current and terminal voltage drop with the fault of the components in the wind power field and the outgoing line by the simulation software of ETAP, and studies the characteristics and fault characteristics of the offshore wind farm. When multiple wind farms are connected to the grid, the wind turbines will provide short-circuit current that cannot be ignored and it will be a bilateral power supply for the short-circuit point. Therefore, considering the characteristics and the low-voltage ride-through capability of the wind turbine, it proposes the protection scheme and the setting principle of the components and lines of the offshore wind farm. The cooperation of the protection program and action sequence of the offshore wind farm model built on the software ETAP is simulated, and the correctness and rationality of the proposed protection scheme and action sequence are verified.