Abstract: CuPc thin films on Al2O3 substrates fabricated by using vacuum evaporation deposition method have been investigated at different conditions such as different deposition rate,different thickness and different substrate temperature.Features of the CuPc thin films were measured by X-ray diffraction (XRD),scanning electron microscopy（SEM）and UV-Vis spectrophotometer technology.Results show that the particle size of CuPc films decreases with the deposition rate increasing,and the thicker the film is,the higher the crystallinity is.The phase transition of the CuPc films occurs around 250℃,so that structures of the films change from the original meta-stable -CuPc into stable -CuPc crystal structure.The crystal structure of CuPc thin films is transformed from orthorhombic -phase to monoclinic -phase.