This work presents the results of our theoretical and experimental studies of the cryogenic electromechanical response in multilayer PZT actuators under direct current (DC)/alternating current (AC) electric fields for hydrogen fuel injectors. A shift in the morphotropic phase boundary (MPB) between the tetragonal and rhombohedral/monoclinic phases with decreasing temperature was determined using a thermodynamic model, and the temperature dependent piezoelectric coefficients were obtained. Temperature dependent coercive electric field was also predicted based on the domain wall energy. The electromechanical fields of the multilayer lead zirconate titanate (PZT) actuators from room to cryogenic temperatures were then calculated, by the finite element method. In addition, experimental results on the DC/AC electric field induced strains for PZT actuators were presented to validate the predictions.