We have studied the ab-plane Raman-active phonons of the bilayered magnetic manganite La2-2xSr1+2xMn2O 7 for x = 0.30 and 0.50. The Raman response was deconvoluted to seven modes in both cases and their symmetries and T-dependence analyzed. We found that the T-dependence of the linewidth and frequency of almost phonons follows the two-phonon anharmonic decay and the usual Grüneisen behavior, respectively, with exception of the 1000 cm-1 mode for x = 0.30 that softens ∼ 150 cm-1 below Tc due to their strong spin-phonon coupling. We also notice that some modes for x = 0.50 before associated to two- and three-phonons Raman process appeared to us as being one-phonon Raman peaks. © 2003 Elsevier B.V. All rights reserved.272-276III17361737Martinho, H., (2003) Phys. Rev. B, 67, p. 214428Pantoja, A.E., (2001) Phys. Rev. B, 63, p. 132406Argyriou, D.N., (1999) Phys. Rev. B, 59, p. 8695Martinho, H., (2002) Physica B, 320, p. 40