  We report the pressure dependence of the structural parameters of the
non-oxide perovskite superconductor MgCNi$_{3}$ up to 32 GPa using a diamond
anvil cell and synchrotron x-rays at room temperature. The structure of the
compound remains in the Pm-3m cubic symmetry throughout the pressure range. The
bulk modulus $B_{0}=156.9\pm0.2$GPa with $B_{0}^{\prime}=9.8$obtained by
fitting the pressure-volume data is in good agreement with theoretical
calculations reported earlier. An anomalous shift of the (111) and (200) lines
observed above 9 GPa indicates a possible local short range distortion that is
consistent with earlier studies.

Superconductivity