This study demonstrated the thermally-assisted (TA) programming of a NOR flash memory device, which was composed of a junctionless silicon nanowire with gate-all-around structure. Fast programming was achieved with the aid of Joule heat, which was generated in a homogeneously heavily doped SiNW by a voltage difference between the source and drain. Its programming speed is the fastest among various NOR flash memories ever reported. The mechanism for programming NOR flash memory inevitably degrades the quality of the tunneling oxide. But the proposed thermally-assisted programming provides simultaneous curing of the damaged tunneling oxide.