Polarized Raman spectroscopy has been used to obtain the room-temperature phonon spectra of the series of rare earth orthovanadate single crystals: $\mathrm{Sm}\mathrm{V}{\mathrm{O}}_4$ , $\mathrm{Ho}\mathrm{V}{\mathrm{O}}_4$ , $\mathrm{Yb}\mathrm{V}{\mathrm{O}}_4$ , and $\mathrm{Lu}\mathrm{V}{\mathrm{O}}_4$ . The observed Raman frequencies follow the overall mode distribution expected for ${\mathrm{REVO}}_4$ compounds with the tetragonal zircon structure. The variation of the mode frequency with atomic number across the lanthanide orthovanadate series was investigated, and the trend exhibited by the internal modes was explained by considering the force constants of $\mathrm{V}{\mathrm{O}}_4$ tetrahedron.