Due to the coupling of piezoelectric and semiconducting dual properties,much attention has been focused on the piezoelectric semiconductor materials,such as ZnO,ZnS,CdS and GaN.With the usage of these piezoelectric semiconductor materials,novel nanodevices have been demonstrated,from which a new field called piezotronics was formulated.The core of piezotronics is to study the mechanism of the piezoelectric effect on tuning the charge transport behavior across various junctions or interfaces,with potential applications in sensors,microelectromechanical systems,and force/pressure triggered electric devices.Here following the theoretical frame work of piezotronic effect,analytical solutions of piezoelectric heterojunction are presented to investigate the electrical transport behavior at a p-n junction.Numerical simulation is given for guiding future experimental measurements. Due to the coupling of piezoelectric and semiconducting dual properties, much attention has been focused on the piezoelectric semiconductor materials, such as ZnO, ZnS, CdS and GaN .With the usage of these piezoelectric semiconductor materials, novel nanodevices have been demonstrated, from which a new field called piezotronics was to study the mechanism of the piezoelectric effect on tuning the charge transport behavior across various junctions or interfaces, with potential applications in sensors, microelectromechanical systems, and force / pressure triggered electric devices. Here following the theoretical frame work of piezotronic effect, analytical solutions of piezoelectric heterojunction are presented to investigate the electrical transport behavior at a pn junction. Numerical simulation is given for guiding future experimental measurements.