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Raman Spectra of single crystals of $Mg(ClO4)2.6H2O$ and $Zn(ClO4)2.6H2O$ are presented for the first time in the region $20-4000cm-1$. $Ar+$ laser (514.5 nm) was used for excitation, and polarization studies were made in all the orientations of the crystals. The observed lines are attributed to the phonons originating form the Raman active modes of isolated $ClO4-(Td)$ and $[M(OH2)6]2+(Th)$ units. The $Th$ symmetry considered for $[M(OH2)6]2+$ complex is found consistent with the known crystal space group, $C2v7$, of the $salts1$ and results is correct symmetry classification of the 174 phonon braches as $48A1+39A2+48B1+39B2$ in the unit cell. It is also shown that the water molecules lie almost in a plane perpendicular to the crystal c-axis. $\mathrm{<mrow\; data-mjx-texclass="ORD">1</mrow>}$M. Ghosh and S. Ray, Z. Kristallogr. 145, 146 (1977).