To provide a torque limiter having high accuracy and longer durability and capable easily changing a blocking value blocking rotary transmission into an optional value.

The torque limiter comprises a rotation receiving portion 1 integrally rotating together with a rotation drive source 50, a rotation transmitting portion 3 making a driven rotary mechanism 51 rotate integrally, and a rotation transmission blocking portion 2 integrally rotatably connecting the rotation receiving portion 1 and the rotation transmitting portion 3. Blocking of rotation transmission from the rotation receiving portion 1 to the rotation transmission blocking portion 2 is carried out by urging and connecting a rolling ring 22 of a passive block body 27 to a locking recessed portion 19 of a rotary block body 10 of the rotation receiving portion 1. When rotary torque of the rotation transmitting portion 3 reaches a designated value, the blocking of rotation transmission is carried out by causing the rolling ring 22 to come off out of the locking recessed portion 19 against urging force of the elastic body 27 and bring the ring 22 into press contact with a rotation transmitting end face 10b of the rotary block body 10 in a rolling state.