The snap off of emulsion drops appears in several industrial activities, including the oil industry. The analysis snap off in a constricted capillary is related to the study of emulsion formation and its characteristics in a porous media. This thesis presents a numerical model based on the conservation equations and lubrification theory developed for Newtonians fluids. The resulting system of differential equations was solved by finite difference and the code implemented in MATLB®. The analysis of the effect of different parameters, such as the geometry of the capillary and the liquid proprieties, indicated appropriate behaviors in comparison to data in the literature. It was observed that the viscosity of the continuous phase fluid has a stronger influence in the snap off time than the viscosity of the dispersed phase fluid. The snap off time rises with the viscosity of the continuous phase fluid. It was observed that the variation of the radius of the neck directly influences the snap off time, where smaller throat radius leads to shorter snap-off time, due to stronger capillary pressure gradient.