The invention provides a butting buffer device used during floating attachment installation of offshore platforms. The device comprises an upper structure and a lower structure, wherein the upper structure comprises a sleeve, a piston receiver arranged inside the sleeve, and a vertical rubber unit sleeved upon a stand column of the piston receiver; the upper part inside the sleeve is relatively connected with a pair of rib plates, a clamping plate which is integrally connected with the upper part of the piston receiver is mounted at the bottom of each rib plate; a cavity is formed upwards in the bottom of the piston receiver, a horizontal rubber unit used for shock absorption is arranged on each of both sides of the bottom of the piston receiver, and the horizontal rubber units are connected with the two sides of the bottom of the piston receiver; the lower structure comprises a sand box arranged at the bottom of the sleeve; an insertion tip is arranged at the upper part of the sand box, an outer sleeve is sleeved upon the insertion tip, and the cavity formed after the insertion tip is matched with the outer sleeve is filled with concrete. The butting buffer device can be installed on land without being affected by changeable marine environment conditions, thereby not only reducing the construction difficulty, but also improving the security of offshore installation of platforms.