CoFe2O4/TiO2 nano-composite films were prepared using the sol-gel method with tetrabutyltitanate and metallic chlorates as starting materials. The phase structure and microstructure properties of the samples were studied by X-ray diffractometer, Raman spectrum, scanning electron microscopy. The magnetic properties of the composite films were characterized by vibrating sample magnetometry. The results show that crystals of different substances grow up independently without producing new phases, and the growth of composite films is dependent on the heat treatment temperature. The grain size of Cobalt ferrite is controlled by the titanium dioxide matrix in the prepared composite films, the average size of CoFe2O4/TiO2 is 19nm in nano-composite film prepared at 800℃ and pH=2-3 of the precursor. The magnetism of the composite films is enhanced with an increase of the heat treatment temperature.