Effect of Mn dopant on energy storage properties in lead-free NaNbO3-0.04CaZrO(3) (NNCZ) thin films was investigated. The leakage current was largely suppressed, whereas dielectric constant, breakdown fields, and the difference between maximum polarization and remnant polarization were improved significantly by Mn doping, resulting in a large enhancement of energy storage performance. A large recoverable energy storage density of similar to 19.64J/cm(3) and an excellent thermal stability (from 30 to 160 degrees C) were simultaneously achieved in the NNCZ thin film with 1mol% Mn addition. Our results ascertain the great potential of NNCZ lead-free thin films for the applications in energy storage devices over a wide temperature range.