A torque transmission device connects two rotary shafts having shaft ends opposing each other, such that torque is transmitted through a torque transmission mechanism provided to a shaft end surface of each of the two rotary shafts. A first rotary shaft of the two rotary shafts has a double-supported structure where both end portions of the first rotary shaft are supported by bearings, respectively. A second rotary shaft of the two rotary shafts has a cantilever structure where only one end portion of the second rotary shaft opposite to the torque transmission mechanism is supported by a bearing, and the second rotary shaft is spaced from one bearing of the bearings supporting the first rotary shaft, the one bearing being provided at a side of the torque transmission mechanism.