To provide a helmet capable of being put on a head without giving a feeling of pressure to the head and useful for eliminating the stuffiness of the head.

This helmet with air bags is obtained by disposing the bag portions of the air bags on at least four portions brought into contact with the head of a human body and further disposing constricted portions between the portions brought into contact with the head of the human body. Thus, a space between the helmet main body 111 and the head H is eliminated by the expansion of the bag portions to prevent the slippage of the helmet. Spaces for the passage of air are thus formed between the helmet main body 111 and the head H due to the constricted portions to prevent the stuffiness of the head.