A robot including a wrist base, a wrist flange member including a flange surface for mounting an end effector, and an actuator driven to rotate the wrist flange member relative to the wrist base around an axis line orthogonal to the flange surface, the actuator includes a first member fixed to the wrist base and a second member fixed to the wrist flange member, a gap which is exposed in a direction opposite to the flange surface along the axis line is formed between a cylindrically shaped outer peripheral surface of the wrist base or the first member and a cylindrically shaped inner peripheral surface, which is arranged radially outside the outer peripheral surface, of the wrist flange member or the second member, and the robot includes an oil seal for sealing the gap.