The nonvolatile memory properties of metal-oxide-semiconductor memory capacitors containing nanocrystalline MoOx embedded ZrHfO high-k gate dielectric have been investigated. The charge trapping capacity and trapping site were investigated using the capacitance-voltage hysteresis and constant voltage stress methods. The memory functions were mainly based on trapping holes at the MoOx site. The current density-voltage curve result confirmed the above charge trapping mechanism and showed the Coulomb blockade phenomena. More than 50% of trapped charges could be retained for more than 10 years. This is a viable dielectric structure for future nanosize memories.