In order to investigate the effect of resin cement interface deterioration on mechanical properties and interfacial microstructure of resin light conductive cementitious materials（RLCCM） under acid rain, transparent resin and cement matrix used as carriers and an accelerated test method of combined action of acid rain and dry wet cycle were adopted, oblique shear bond strength, surface appearances were used to obtain the corrosion regularity and ESEM EDS was used to analysis the deterioration mechanism of resin cement interface under acid rain. The results show that oblique shear failure of specimens occurs at the resin cement interface, oblique shear bond strength of resin cement interface first increases and then declines after exposed to combined action of acid rain and dry wet cycle; cement matrix starts to corrode at the position close to the interface, with the growth of the age, corrosion occurs from the surface to the interior of materials; after exposed to combined action of acid rain and dry wet cycle, CH is gradually reduced and gypsum is generated to fill partial pores at the early days, making the resin cement interface denser, with the increase of time, C S H is gradually reduced, more and more gypsums are generated, the areas close to resin cement interface is covered with a layer of white viscous gypsum, resulting cracks in the interface.