Due to its flexibility, small size and low cost, the nanomaterials films are widely desired in optical applications. In this study, a solid nanodiamond (ND) film was fabricated and characterized for photonics applications. The nanocomposite films were prepared by drop casting method where ND was embedded into poly Vinylidene fluoride-trifluoroethylene (PVDF-TrFE) as a host polymer. Both physical and optical properties of the prepared film were investigated. To analyze the structure of fabricated ND-PVDF-TrFE film, various measurement methods were adopted, including a field emission scanning electron microscopy (FESEM), Fourier transform spectroscopy (FTIR), and x-ray diffraction. The nonlinear absorption property of ND-PVDF-TrFE film was studied by balanced twin detector technique (BTDT) using mode-locked fiber laser with pulse width of 1.4 ps at wavelength of 1566 nm. The results showed that the saturable-absorption features of ND-PVDF-TrFE film possess a good nonlinear performance. Furthermore, a good nonlinearity with a high modulation depth makes the ND-PVDF-TrFE film a good candidate to use in many photonics systems such as saturable absorber (SA) in passive Q-switched or mode-locked fiber lasers.