Abstract: In this paper, the fire protection design of offshore wind farm is established, including the offshore wind turbines, offshore wind farm substation and land control center building. Each offshore wind turbine, offshore wind farm substation and land control center building set up independent fire alarm system, mainly adopt the suction type smoke detector and point type compound smoke temperature detector for the confirmation of the secondary alarm. At the same time, their fire extinguishing system are: high pressure CO2 fire extinguishing system, water mist fire extinguishing system and water spray extinguishing system respectively. Finally, combining with an engineering case, the fire protection design of offshore wind farm is designed specifically.