The fundamental study of rheological properties of fluid is carried out by the approach of dam-break flow problem. Based on the finite extent dam-break flow model, the flow characteristics of fluid are investigated. Dam break flow has been the subject of extensive research for a long time. The original problem has direct application in the industrial areas of fluid mechanics and environment protection where the intrusion of gravity flow is analogous to the propagation of front wave in the dam-break flow problem. In this study, the characteristic of Newtonian fluid is investigated by using the dam-break flow model. The dam-break flow model is simulated using a two-dimensional numerical model based on the Marker and Cell (MAC) method. The propagation of the front wave and the attenuation of the depth at the origin are used as parameters to characterise the rheological properties of the fluid.