In the paper, the Ce doping is proposed to improve the thermal stability and increase the resistance in ZnSb thin film for phase-change memory (PCM) application. By Ce doping, it is proved that the resistance of amorphous and crystalline state, crystallization temperature (Tc), 10-year lifetime temperature (Tten) and activation energy (Ea) were significantly increased in ZnSb films. The improvement of thermal stability and the reduction of reset current were achieved. Through the experimental investigation, the new formation of Ce–Sb bonding by Ce doping was found in the Sb hexagonal structure, which might be the key reasons for the enhanced performance.