A multiple parallel plate aluminum ionization chamber has been designed for the study of dose distribution at and near the interface of different materials.The measurement of dose gradient distribution at and near the interface of Kovar/Au/Al,Pb/Al,Ta/Al has been done for 30—100 keV X rays from the synchrotron radiation source, and the dose enhancement factor(DEF) are also provided. DEF for interface of different materials is calculated by Monte-Carlo simulation of particle transportation, and the results are consistent with the measured dose-enhancement factor. A reliable evaluation approach of theoritival and experimental method is proposed for studying X-ray dose enhancement.