The electrical resistance on the crystallization process of sputtered-deposited Ge1Cu2Te3 film was investigated by a two-point probe method. It was found that the amorphous Ge1Cu2Te3 film crystallized into a single Ge1Cu2Te3 phase with a chalcopyrite structure, which lead to a large resistance drop. The crystallization temperature of the Ge1Cu2Te3 amorphous film was about 250°C, which was about 70°C higher than the conventional Ge2Sb 2Te5 amorphous film. The activation energy for the crystallization of the Ge1Cu2Te3 amorphous film was higher than that of the Ge2Sb2Te5 amorphous film. The Ge1Cu2Te3 compound with a low melting point can be expected to be suitable as a phase change material for PCRAM.