Polarized first-order Raman scattering studies at 300 K were carried out in L-asparagine monohydrate crystal in order to obtain the general assignment of its phonon spectra. A careful analysis of the vibrational spectra shows that the assignment of the fundamental vibrational modes can be done on the basis of amino, carboxilic and water groups vibrations, and correlations with previous data reported for other amino acids. However, some vibrations were correctly assigned from the study of its temperature - dependence behavior performed in the range 10 - 300 K. The assignment proposed cofirm the zwitterionic structure of L-asparagine monohydrate crystal