The utility model provides a road bridge expansion joint belongs to bridge facility field. It has solved the poor problem of current expansion joint shock attenuation effect. This road bridge expansion joint, including left base and the right base of being connected with left bridge and right bridge respectively, be equipped with a plurality of left broachs and a plurality of right broach on left side base and the right base respectively, a plurality of left broachs and a plurality of right broach misplace each other and form tenon fourth of the twelve earthly branches structure, left side broach front end and right broach front end are equipped with the slot respectively, the post is inserted in the slot interpolation, it is equipped with compression spring to insert between post and the slot tank bottom, compression spring promotes the post of inserting in the left broach, the messenger inserts the post outer end and supports on right base, and keep off on the gap between adjacent right broach rear end, compression spring promotes the post of inserting in the right broach, the messenger inserts the post outer end and supports on left base, and keep off on the gap between adjacent left broach rear end. This expansion joint can avoid the gap too big, makes the vehicle produce too big vibrations, also can avoid advancing sand at the slotted section through inserting the post simultaneously.