A joint drive type link mechanism provided with a link including a joint portion at an intermediary thereof, and a driving source for the joint portion, wherein a link member configuring the link is mounted with the driving source and electric components used for the control of the driving source, in which the link is prevented from being heated by the heat of the electric components is provided. The link member includes an interior space in which the electric components are arranged and has the driving source is arranged thereon with an air inlet connecting to the interior space and an exhaust outlet for exhausting the air passing through the interior space. Further, the interior space is provided with fans as well as a heat sink for cooling the air after air-cooling the electric components.