Disclosed is an organic non-volatile memory (ONVM) material including nanoparticles evenly dispersed in a first polymer. The nanoparticles have a metal core covered by a second polymer to form a core/shell structure, and the first polymer has a higher polymerization degree and molecular weight than the second polymer. The ONVM material of the invention has high uniformity, thereby stabilizing the electric properties of the memory device, such as increasing rewrite counts, increasing data retention time, reducing driving voltage, reducing write current, and enhancing current on/off ratio.