FeCN thin films were prepared using a targeted magnetron sputtering system, and the effects of Fe doping on the bond states, friction properties, and thermal stability of carbon-nitrogen thin films were studied. It was found that the doping of Fe element can increase the ratio of N-SP3 to N-SP2 in the film, which is beneficial for the formation of the β-C3N4 phase. For the first time, it was found that moderate doping can reduce the friction coefficient of carbon-nitrogen films but the thermal stability of FeCN films has decreased. The mechanism for improving the friction coefficient of thin films may be due to the increased proportion of sp3 bond states in the films.