Abstract: To investigate the relatlonship between the structure and the photophysics property of PPV/TiO2, gel composite, a series of PPV/TiO2 gel composites were prepared by employing a sol-gel process. The structure and the photophysics property of the composite were studied by FTlR, UV-VIS, FL spectra and TEM. When the TiO2 gel content increased, the TiO2 network structure formed and the effective conjugation length in the PPV/TiO2 gel composite shortened, correspondingly the luminescence emission shifted to shorter wavelength and the luminescence intensity enhanced in the composite. TiO2 gel structure and effective conjugated length of the PPV/TiO2, gel composite can control the photophysics property of the composite.