The invention relates to the technical field of passive safety devices of automobiles, in particular to an overhead air bag device. The overhead air bag device comprises a gas generator and an overhead air bag module which are mounted in an automobile roof, wherein a folded air bag is placed in the overhead air bag module, an inner pull tape is arranged in the air bag, two fixing points are arranged on the outer side of an air bag main piece, and two ends of an outer pull tape are fixed on the two fixing points respectively. Compared with the prior art, the overhead air bag device has the advantages that the unfolded shape of the air bag on the copilot side can be kept stable all the time and the self-supporting function is realized under the action of the inner pull tape and the outer pull tape, support from a dashboard is not required, and influences of modeling design of the dashboard are cast off. The outer pull tape is added to the outer side of the air bag, the air bag can have tension in different directions by means of the outer pull tapes in different positions, moment resisting rotation of the air bag is generated or the contact position and area of the air bag with windshield glass are controlled, and dissymmetric support force is reduced.