  We report the first principle calculations of the lattice dynamics of
KNi$_{2}$Se$_2$ together with the Raman scattering study.\ We have observed
three out of four Raman active modes predicted by the factor group analysis.
Calculated phonon frequencies are in good agreement with experimental
findings.\ Contrary to its iron counterpart (K$_x$Fe$_{2-y}$Se$_2$),
K$_{0.95}$Ni$_{1.86}$Se$_2$ does not show vacancy ordering.
