A torque measuring device for a flywheel, the torque measuring device adapted to be mounted on a frame of an exercise bike which has the flywheel , a wheel shaft mounted through the flywheel , and a transmission mechanism driving the flywheel , the torque measuring device adapted to be connected to the flywheel , the wheel shaft , and the transmission mechanism , and the torque measuring device comprising: a base rotatably mounted on the wheel shaft and having a combination portion ; and a connection portion attached to the combination portion and having an outer peripheral surface ; and a transmission portion disposed next to the connection portion and connected to the transmission mechanism ; and a measuring assembly mounted on the wheel shaft and the base and having a magnet mounted on the wheel shaft ; and multiple torque measuring apparatuses mounted on and arranged around the outer peripheral surface of the connection portion of the base ; and a communication module mounted on the combination portion of the base and receiving and outputting measurement data measured by the measuring assembly ; and a power module mounted on the combination portion of the base and providing electricity to the communication module and the multiple torque measuring apparatuses , and characterized in that : the combination portion has a first side fixed to the flywheel ; and a second side opposite to the first side ; the connection portion is attached to the first side of the combination portion ; the communication module is mounted on the second side of the combination portion without being shielded by the flywheel ; and the power module is mounted on the second side of the combination portion without being shielded by the flywheel . a base rotatably mounted on the wheel shaft and having a combination portion ; and a connection portion attached to the combination portion and having an outer peripheral surface ; and a transmission portion disposed next to the connection portion and connected to the transmission mechanism ; and a combination portion ; and a connection portion attached to the combination portion and having an outer peripheral surface ; and a transmission portion disposed next to the connection portion and connected to the transmission mechanism ; and a measuring assembly mounted on the wheel shaft and the base and having a magnet mounted on the wheel shaft ; and multiple torque measuring apparatuses mounted on and arranged around the outer peripheral surface of the connection portion of the base ; and a magnet mounted on the wheel shaft ; and multiple torque measuring apparatuses mounted on and arranged around the outer peripheral surface of the connection portion of the base ; and a communication module mounted on the combination portion of the base and receiving and outputting measurement data measured by the measuring assembly ; and a power module mounted on the combination portion of the base and providing electricity to the communication module and the multiple torque measuring apparatuses , and characterized in that : the combination portion has a first side fixed to the flywheel ; and a second side opposite to the first side ; the connection portion is attached to the first side of the combination portion ; the communication module is mounted on the second side of the combination portion without being shielded by the flywheel ; and the power module is mounted on the second side of the combination portion without being shielded by the flywheel . the combination portion has a first side fixed to the flywheel ; and a second side opposite to the first side ; the connection portion is attached to the first side of the combination portion ; the communication module is mounted on the second side of the combination portion without being shielded by the flywheel ; and the power module is mounted on the second side of the combination portion without being shielded by the flywheel . <EOS>