In this paper, properties of nanocomposite films which were prepared from a new polyimide and SiC nanoparticles via two simple methods are reported: (1) SiC nanoparticles were firstly functionalized with epoxide-end groups (mSiC) and then solution blended with poly(triazole-imide) (PTAI) in DMAc. The homogeneous solution was heated in vacuum to give PTAI/mSiC film. (2) A new diamine containing 1,2,4-triazole ring and a commercial dianhydride was reacted in situ in the presence of native SiC nanoparticles to give a homogeneous poly(amic acid) PAA/SiC mixture which was then heated in vacuum under high temperature thermal process to give PTAI/SiC film. The nanocomposite films were tested for different properties including thermal using TGA and DMTA, mechanical and photophysical. The results showed that strong chemical bonding between SiC nanoparticles and the polymer matrix contributed to the enhanced Tg from 300 °C to >350 °C, tensile strength from 108 MPa to 165 MPa and temperature of 5% weight loss (T5%) from 380 °C to 500 °C. The photoluminescence intensity of the nanocomposites increased and the spectra showed blue shift with increasing SiC content.