Nitrogen doping of fluorinated diamond-like carbon (FN-DLC) thin films were prepared by radio frequency plasma enhanced chemical deposition (RF-PECVD) under different radio frequency power (RF-power) with CF4, CH4 and nitrogen as source gases. The sp hybrid structure and chemical bond structure of the films were characterized by Auger electron spectroscopy, Raman spectroscopy, X-ray photoelectron spectroscopy and Fourier transform infrared absorption spectrometry, and the sp2/sp3 hybrid ratios were analyzed by fitting multi-peaks of Gauss an form. The results show that the thin films are a type of diamond-like carbon films. The sp2/sp3 hybrid ratios in the films deposited by different RF-power lie between 2.0 to 9.0. The sp2 structure in the films increases with the increasing RF-power. The chemical bond structure in the films are C—Fx(x=1,2),C—C, C=C and C≡N. The C—C bond increases with the increasing RF-power, while the C—F bond decreases. Higher RF-power is shown to reduce the F content in the films. The degree of cross-linking in the films is enhanced and the films become more stable with increasing RF-power.