Interfacial delamination is one of the most common failure modes in electronic packages. To obtain good reliability of electronic packages, it is important to study the interface properties. In this study, the adhesion reliabilities of the epoxy-Cu interface, which is widely used in electronic packagings, are investigated using molecular dynamics simulation with the effects of temperature, moisture, crosslink conversion, and oxidation degree considered. The results show that adhesion reliability of Cu-epoxy interfaces is almost independent of temperature, strain rate, and crosslink conversion of epoxy resins, while is weakened by increasing moisture contents. The variation of interfacial interaction energy with the increasing tensile deformation is revealed at molecular scale, which is useful to understand the interfacial interaction and interfacial delamination.