Aiming at the functional defects in the inflation of current landing cushion airbags, this paper designed and studied a new type of self-inflating airbag. The structure and self-inflation principle of the airbag were introduced, and the overall structural model of the airbag was established. The structure of the inlet and its working principle were analyzed and related calculation was conducted. Finally, the landing process of the airbag and its buffering properties were theoretically analyzed. Only 1/6 volume of the new self-inflating landing cushion airbag needed to be inflated by its own gas source, and the inlet structure could satisfy the self-inflation of the airbag when airdropped. An example was given and the maximum shock acceleration of the airdrop loads was calculated to be only 60 m/s2, which was less than the allowable value. The new self-inflating airbag could greatly reduce the weight of the airdrop system itself, the inlet structure could meet the require? ments of airbag function, and the maximum shock acceleration of the airdrop supplies was less than the allowable value. The airbag could play a very good role in protecting the airdropped goods.