The interface interaction between epoxy adhesive (E-51) modified with earboxyl-terminated liquied butadiene-acrylonitrile rubber (CTBN) and aluminum surface has been studied by reflection-absorption infrared spectroscopy．Our spectroscopic results indicated that significant difference in the shear strength of adhesive-aluminum joints formed by using imidazole (EWI2

4) and m-phenylene diamine as curing agents can be at-tributed to their differences，in the interfacial structure．As it was shown from the reflection-absorption spectra，the aluminum film peeled from the latter adhesive joint，i.e. one cured with m-phenylene diamine．is tom prised of CTBN as the main component at the interface.