A passenger airbag apparatus for a vehicle includes a retainer, an airbag folded and retained in the retainer, a deployment-limiting sheet, and a shape-retaining sheet. The deployment-limiting sheet has one end coupled to the retainer or the rear portion of the airbag, and extends toward the front portion of the airbag while being superposed on the airbag. The deployment-limiting sheet has a first folded part and extends along the rear portion of the airbag during inflation of the airbag. The first shape-retaining sheet is coupled to the retainer or the deployment-limiting sheet for retaining a shape of the folded airbag and a shape of the deployment-limiting sheet. The first shape-retaining sheet has a shape-retainment release portion for releasing a shape of the folded airbag by inflation of the airbag.