Polarized Raman spectra of all four symmetry species in single crystal LiB3O5 have been measured at room and high temperature. The vibrational modes are classified by the method factor group analysis and the internal vibration bands are tentatinely assigned to vibrations of BO3 triangle and BO4 tetrahedron. Based upon the experimental results of LO-TO splitting , the effective charges of polar modes and the static dielectric constants are calculated.