Abstract: A resistance device includes a first rotating assembly having a first rotating member, and a second rotating assembly having a second rotating member and a plurality of magnets. A transmission unit is connected to one of the rotating assemblies for driving rotation of the same. A drive unit is connected to the other one of the rotating assemblies, is configured to receive a control signal, and is configured to drive rotation of the other one of the rotating assemblies according to the received control signal. Eddy currents generated by the first rotating member provide resistance to the transmission unit. A resistance training machine having the resistance device is also disclosed.