A head protecting airbag device according to the present invention includes a gas admissive portion and a non-admissive portion. The gas admissive portion includes a gas feed passage disposed along the upper edge of the airbag, and an inflatable shielding portion located below the gas feed passage for covering the inner side of the windows upon deployment. The inflatable shielding portion includes a plurality of protection portions and a plurality of vertical passages vertically disposed in the front and rear of each of the protection portions. The protection portions are juxtaposed along the front-rear direction of the vehicle. The vertical passages are communicated at upper ends with the gas feed passage. Each of the protection portions admits inflation gas via the vertical passages.