The invention discloses a telescopic device for a comb-tooth-type vibration-absorbing displacement bridge support, which structurally comprises a first comb, rubber layer, second comb, steel bar, A lay of rubber is arrange between that first comb teeth and the second comb teeth, At that cent of the rubber lay, the sliding buckle is matched with the teeth of the first comb or the second comb, the first comb teeth and the second comb teeth are horizontally provided with more than two reinforcing bars facing away from the side surface of the rubber layer, steel bar and rubber layer are welded horizontally, As that first comb tooth, rubber layer, second comb fitting, using overlapping rubber layers to align the first comb teeth, The first comb teeth and the second comb teeth are reversely pushed apart to reduce the crossing depth when the concrete shrinks, so that the reinforcing bars of the first comb teeth and the second comb teeth penetrate into the concrete of the bridge bearing, thereby preventing the bridge bearing from being detached from the bridge bearing after long-term use and temperature change, thereby reducing the load force.