An inverse opal structural molecular imprinted photonic crystal(MIPC) sensor was established by combining the responsive photonic crystal and molecular imprinting techniques.The 3-D opal structure was obtained by vertical deposition self-assembly of monodisperse silica nanospheres which were prepared by St’ber method.MIPC was obtained after removing SiO2 nanospheres and imprinted molecules.Scanning electron microscope showed that the MIPC possessed a highly ordered 3-D macroporous structure.The recognition for target analytes could be directly transferred into readable optical signals through a fiber optic spectrometer.The factors,such as eluate,pH value,sample matrix and molecular imprinted polymer(MIP) synthesis conditions,were optimized to improve the recognition ability and sensing properties of MIPC sensor.The MIPC sensor showed a good selectivity to ethyl paraben against interferons(2-hydroxy isobutyric acid,benzocaine and procaine) studied.Under the optimized conditions,the shift value of Bragg Diffraction peak of MIPC sensor was linearly related with the concentration of ethyl paraben.The sensor could be re-used with well performance,and the quantitation limit is 83 mg/L.The MIPC sensor could be applied directly and conveniently in monitoring of the target analytes in complex samples with good accuracy and sensitivity,and there is no need for sample processing.So it is suitable for on-site rapid screening and detection.