The utility model provides a prevent lubricated wind device of external height of bed temperature of CFB boiler coking, includes the electrical control valve, goes up manual governing valve, lower manual governing valve, lubricated tuber pipe of riser and the lubricated tuber pipe of side wall, manual governing valve is gone up, the flow and the pressure head of lower manual governing valve control lubricating wind to the electrical control valve, the lubricated tuber pipe of riser around riser installation, the branch pipe is equidistant to be arranged, the lubricated tuber pipe of side wall on the branch pipe arrange in external bed casing side wall and partition wall to go up the structure and constitute lubricated wind device jointly, can intermittent type or continuous operation, the utility model discloses the effective control circulation ash returning charge volume of riser and external bed, solved the problem of the external height of bed temperature of CFB boiler coking to ensure external bed safety, reliability service.