An explosion clad plate composed of copper and mild steel is dealt with as a typical example of the bonded dissimilar plate. Tensile tests are carried out at various temperatures by using rectangular plate specimens extracted from the clad plate. Each specimen has an artificial through-the-thickness edge crack close and perpendicular to the explosive interface. The crack mouth opening displacement and the fracture strength are experimentally examined. Stress, strain, plastic zone near a crack and the crack opening displacement are also examined by the analysis. The effects of the material inhomogeneity, the residual stress and the hardened zone on deformation and fracture are revealed. The deformation near a crack tip is basically influenced by the material inhomogeneity, the residual stress and the hardened zone ahead of the crack tip. The fracture strength of the inhomogeneous specimen whose crack-tip material is mild steel is lower at a relatively high temperature although it is almost the same at a low temperature when compared with that for the homogeneous mild steel. The fracture strength of the inhomogeneous specimen whose crack-tip material is copper is higher than that for the homogeneous copper throughout all the test temperature range.