A lubrication mechanism for a bearing is provided having an outer race; an inner race located radially inward of the outer race; a rolling element interposed between the outer race and the inner race; and a pair of shield members provided on both sides of the outer race and the inner race. The outer race, the inner race and the pair of shield members define an interior space located inside the pair of shield members and an exterior space located outside the pair of shield members. The interior space is filled with lubricant. A communication hole communicating between the interior space and the exterior space is formed in the pair of shield members, and a guide portion that guides the lubricant in the interior space to the exterior space through the communication hole.