The invention provides a bearing roller chain for a seal mechanism, which has the advantages of full seal performance, preventing the outside foreign objects from entering into, increasing the outside lubricant leakage prevention, increasing the abrasion resistance and service life, and restraining the poor rotation of the roller. A seal mechanism is arranged between the inner link plate (5) of abearing roller chain (1) and a bearing roller assembly (6) carried by the link plate. The bearing roller assembly is formed by arranging a plurality of anti-friction rollers (11) between a hollow roller (10) and a bush (7). The seal mechanism (9) comprises an annular oil seal member (13) , a spacer (14) and a seal member (15) having a flange (15b) extended toward the outer side surface of the hollow roller loosely into an outer circumferential concave groove on the end surface of the hollow roller. The seal member (15) closely comes into close contact with the inner link plate (5) and the spacer (4) respectively. The flange (15b) enters into the concave groove (10c) formed on the outer side of the roller with gaps remained so as to form a labyrinth structure (16).