The invention discloses a guide rail buckle assembly for a sliding door system. The guide rail buckle assembly comprises a guide rail buckle seat plate and a guide rail buckle ring, wherein the guide rail buckle seat plate comprises a buffering part, a connecting part and a guide part; the buffering part is provided with a guide rail lock buffering block, and is clamped and fixed by a reinforced hoop; the guide rail lock buffering block is formed after carrying out encapsulation treatment on the outer surface of a buffering block insert shaft; and the connecting part is positioned in a neck position of the guide rail buckle seat plate. The reinforced hoop can effectively support the impacted guide rail lock buffering block, so that the stability is improved; the buffering block insert shaft can bear an impact force of an automobile door, so that the service life is increased. The guide rail buckle assembly can exert the function of a motion rail for an automobile sliding door, is high in integrated degree, and reduces the assembling difficulty. In addition, the guide rail buckle assembly exerts buffering and shock absorption functions after the automobile sliding door is opened, and a buckle is buffered uniformly when the automobile sliding door is opened, so that the service life of the buckle is prolonged, and shock deformation borne by the automobile sliding door is reduced.