To explain the breakup Process of spherical liquid droplets by shock leave loading, the deformation and breakup of a cylindrical wafer column, impinged by a planar shock wave, were investigated both experimentally and numerically. Experiments were conducted in a 4 mm X 150 mm shock tube equipped with double-exposure holographic interferometer. The cylindrical water column, having a diameter of 4.8 mm and a height of 4 mm, was exposed to a planar shock wave of Mach number 1.47 in atmospheric air. Weber and Reynolds numbers corresponding to these conditions were 6900 and 1.22 X 10(5) respectively. Density changes inside the water column were estimated from interferometeric fringes, and its deformation and breakup process were also evaluated from the interferograms. Numerical results were obtained by solving the Euler equations using the cubic interpolated pseudo-particle (CIP) method to treat a two-phase flow-field consisting of compressible and incompressible fluids. The results show quantitatively good agreement for density variation in be gaseous phase, whereas for the liquid phase, numerical density distributions show only qualitative agreement with experimental ones.