Abstract: A sol-gel in-situ method was used to synthesize the nano-ZnS/PVDF composite film by using ZnAC₂ ·2H₂O and PVDF as the primary materials, and DMF as the solvent. The results analyzed by XRD and TEM exhibit that the ZnS nanoparticles are well distributed in PVDF films and their size can be controlled in the range of 3nm to 7nm. The studies on the UV-VIS absorption spectroscopy show an observable blue-shift with the decrease of the crystal size of ZnS. The fluorescence spectroscopies indicate both the photoemission of recombination with the exciton peaking at 368nm and the emission at 429nm termed 'self-activated’. The optical properties of this composite film are not essentially impacted by adding of dispersant, but the growth of ZnS is limited and the dispersity of these nanoparticles is improved.