Liquid film thickness is measured by moire´ topography which monitored liquid surface. Moire´ fringe measurement techniques share the inherent simplicity found in optical interferometric techniques have the advantage of use over a greater range of displacement. Moire´ fringe are the geometric interference patterns observed when two dense line grating are superposed. Light transmitted through a fixed line grating is deviated by the liquid film surface, producing a distored image of the grating. The moire fringe produced by projection of this optically distored grating onto a second stationary grating permit visualization of the liquid surface and measurement of the liquid film thickness. This study measured the small amplitude of liquid film thickness to the moir~ fringe pattern produced when spherical metal was dropped glycerin pool. And the measurement of liquid film thickness flowing down an inclined plate are required to calculate the liquid surface slope in a position.