Ternary blend film of conjugated polymer, fullerene and inorganic nanoparticles has intensively studied as active material for high power conversion efficiency (PCE) of hybrid solar cells. The mixing of two electron acceptor materials consisting of organic fullerene and inorganic nanoparticles with electron donor conjugated polymer is strongly believed can improve the PCE of solar cells. This ternary blend will increase exciton dissociation efficiency due to the increase of interface area between donor and acceptor materials where exciton dissociation takes place. We have studied optical, structural and morphological properties of ternary thin films containing blend of conjugated polymer poly(3-hexylthiophene (P3HT):fullerene derivative PCBM:Zinc oxide nanoparticles (ZnO-NPs) by measuring their optical absorption, crystal structure and thin film surface morphology. The aim of this research is to ensure that the P3HT, PCBM and ZnO-NP are well mixed both in solutions and in thin films. The ZnO-NP was prepared by using sol-gel method. The average particle size of ZnO-NP is 40 nm as derived from UV-Vis spectrum and confirmed with TEM image. Thin blend films were prepared by using spin-coating method. The UV-Vis spectra show that conjugated polymer P3HT, PCBM and ZnO-NP are well mixed both in solutions and in thin films. Moreover, the well mixed of these three materials are also verified by the XRD pattern and SEM image of the ternary blend film.