Current-voltage and conductance-voltage (G-V) measurements on three-layer Al∕C60∕CdSe nanoparticles∕C60∕indium tin oxide (ITO) structures fabricated by using a spin-coating method showed a nonvolatile electrical bistable behavior. Capacitance-voltage (C-V) measurements on Al∕C60∕CdSe nanoparticles∕C60∕ITO structures showed a clockwise hysteresis with a flatband voltage shift due to the existence of the CdSe nanoparticles, indicative of memory effects in the devices. Current-time measurements showed that the devices exhibited excellent memory retention ability at ambient conditions. Possible operating mechanisms for the memory effects in the Al∕C60∕CdSe nanoparticles∕C60∕ITO devices are described on the basis of the G-V and the C-V results.