The fully enclosed oxygen helmet protection system is mainly suitable for the environment with heavy air pollution, such as sand blasting, spraying, industry and mining. The compressed air is used for forced ventilation, and the moisture, oil gas, rust and small impurities in the air are effectively filtered out through the breathing filter, and then transported to the temperature regulating pipe through the gas pipeline to regulate the cold and warm temperature of the input air, Then input the helmet for the operator to breathe. This set of protection system can effectively isolate the air in the working environment from the breathing air, so as to provide maximum protection for the operator.