Abstract We investigated the effectiveness of AC poling (ACP) processes for [001] direction oriented Pb(Zn1/3Nb2/3)O3-0.055PbTiO3 (PZN-PT) single crystals (SCs) and obtained dielectric constant ε33T/ε0 of 6680 and piezoelectric strain constant d33 of 2760 pC/N, piezoelectric charge constant g33 of 46.7 × 10-3Vm/N, and a figure of merit (FOM) (d33 × g33) of 129 × 10-12m2/N. These values were 19%, 31%, 10%, and 45% higher than those of DC poling PZN-PT SC, respectively. Phase change temperature Tpc, Curie temperature Tc, and acoustic impedance (Z33) of the ACP PZN-PT SC were 121 oC, 165 oC, and 30.5 MRayls, respectively. Compared with Pb(Mg1/3Nb2/3)O3-0.3PbTiO3 SCs, the higher Tpc, Tc, FOM and lower Z33 of the PZN-PT SCs enable the applications in high temperature with better Z33 matching to water and human body, and these findings are vital for a wide range of ultrasonic transducer applications.