Epoxy resins with various ratios from two kinds of curing agents, ethylenediamine (EDA) and N,N’-dimethylethylenediamine (MeEDA), were prepared. In order to examine the strain rate and temperature dependence of the shear yield strength and the shear strength, test specimens were subjected to shear deformation at various strain rates and temperature. The shear yield strength and the shear strength increased almost linearly as the logarithm of the strain rate increased. The strain rate-temperature superposition held for these shear properties. In particular, an experimental equation of the strain rate-temperature superposition for the shear yield strength was found. The shift factor to obtain a master curve was given with the temperature dependence of an Arrhenius type. Furthermore, the strain rate-temperature-mixing ratio of curing agent superposition held for the shear properties, and the shift factor for these superpositions increased with the increase in MeEDA.