The amorphous boron-carbon-nitrogen (BCN) films were deposited by RF magnetron sputtering from a mixed target composed of h-BN and graphite. The growth temperature ranged from 250 to 550 degreesC. This deposition temperature was shown to have significant effect on the composition and elemental binding states of the BCN films, i.e. the films with higher fraction of sp(3) bindings of boron, carbon and nitrogen were obtained at higher deposition temperatures. The refractive index of the BCN films deposited under the above conditions were in the range of 2.1-2.4, and their optical bandgaps ranged from 1.48-2.00 eV. The amorphous B25C40N35, films which were deposited at 550 degreesC, possessed superior optical properties.