The invention relates to a method for preventing continuous collapse of a shield tunnel and structural failures of a tunnel lining. A guide rail is longitudinally laid on the inner wall of the tunnellining, and an inflatable airbag device is adopted to prevent the continuous collapse of the shield tunnel and the structural failures of the tunnel lining; the inflatable airbag device comprises an airbag, an airbag box for accommodating the airbag in a folded state, an inflation device and a control system. In the excavation construction process of the tunnel, a displacement sensor measures thedistance between the tunnel and an excavation surface, when the distance is longer than a preinput standard distance, the airbag box moves forward, and the standard distance is kept; when a sudden situation happens in the construction process of the tunnel and the measured distance is shorter than the standard distance, whether or not a falling object exists is judged, the inflation device is controlled to be started, and whether or not the inflation device can stop inflation is controlled according to an air pressure measurement signal of an air pressure sensor at an air injection port of theairbag box.