The normal, medium and high temperature curing agents were combined as mixed curing agent for the room temperature curing reaction of epoxy resin, and then the post-curing was induced by the environment temperature rising process. The effects of non-reactive diluent dibutyl sebacate on the curing performance of the epoxy resin were analyzed. Flat-knife method, DSC analysis, curing degree test and DMA analysis were taken to evaluate the changes in curing time, process of curing reaction, degree of cure and thermal endurance properties, respectively. In addition, the mechanical properties at normal and high temperatures of the epoxy resin composites were studied through three-point bending test. Results show that the room temperature curing epoxy resin described in this paper possesses a key characteristic in environment temperature rising process. The gradient curing reactions are taking place in the system. After the diluent is added into this system, the extension rate of curing time reaches 37.5% at 25 ℃. The diluent helps to reduce the rate of curing reaction, improve the curing degree and energy storage modulus of the room temperature cured epoxy, but obviously cause decrease in the glass transition temperature. After the environment temperature raising process, the influences of diluent on curing degree and energy storage modulus are weakened, however, reduce in glass transition temperature is more obvious. Dibutyl sebacate used as diluent can significantly improve the bending strength of epoxy resin composites, but is not conducive to maintain the mechanical properties at high temperature.