Metal-free phthalocyanines(H₂Pc) and its derivatives are an important organic electro and photo active material with remarkable chemical stability and flexibility offering considerable interest for many intensive applications. The complexity of the molecule makes the vibrational study of the Raman spectrum difficult. A vibrational assignment of the frequencies in the F.T Raman spectrum of H₂Pc has been made in comparison with its metal derivatives, other related porphyrin, pyrrole, indole and ortho-subsituted benzene structures.