Highly strained PbVO3 films have potential applications in pyroelectric sensors and optoelectronic devices. To understand how strain influences the nonlinear optical characteristic of PbVO3, highly distorted tetragonal PbVO3 epitaxial thin films were grown on LaAlO3 and SrTiO3 substrates. Using Raman scattering spectroscopy, theoretical and experimental studies on the phonon spectra yield insights on the strained structures of V-O apical bondings. Effects of applied strain on the linear optical properties of PbVO3 thin films were experimentally characterized by spectroscopic ellipsometry. Second-order nonlinear susceptibility tensor components of PbVO3/SrTiO3 thin films were determined to be almost twice as large as those of PbVO3/LaAlO3 thin films.