A passenger protection apparatus includes an inflator and an airbag. The inflator configured to supply gas and the airbag is configured to deploy to surround a sitting position, of a passenger by the gas supplied from the inflator. One end of the airbag is supported on an upper portion of a vehicle. The airbag includes a main airbag configured to deploy around the sitting position of the passenger, and a sub-airbag configured to deploy on an inner wall surface of the main airbag.