A parallel link mechanism includes proximal end side and distal end side link hubs, and three or more link mechanisms. Each link mechanism is a trinodal link mechanism including four revolute pairs, and includes proximal side and distal side end link members and an intermediate link member. In each revolute pair of the link mechanism, a pair of pair constituent members is connected to each other via a bearing. A shaft portion provided in one pair constituent member is fitted on an inner periphery of an inner ring of the bearing, and an annular inner face forming portion provided in the other pair constituent member is fitted on an outer periphery of the outer ring of the bearing. The shaft portion and the annular inner face forming portion define a sealing structure which regulates flow of a lubricant between inside and outside of the bearing.