The effects of hot poling treatment on properties and behavior of sol-gel based PZT Pb(Zr 0.52 , Ti 0.48 )O 3 piezoelectric thin films have been investigated. Optimal hot poling conditions (temperature, bias voltage) have been determined to induce largest imprint and to improve piezoelectric properties. The effective piezoelectric coefficient e 31,eff is enhanced by about 22% after poling. The stability of poling state has been studied as a function of time. Effects of poling on actuators behavior have finally been observed such as higher actuation efficiency, with about 22% more deflection after hot poling, as well as lower hysteresis.