Internal erosion and seepage in earth dams is known as a major parameters of dam break and investigation on these phenomena is of important issues in monitoring and surveillance of dams. Numerical modelling of seepage in dams’ body and determining the highest level of seepage line (phreatic) is one of the finest remedies in this field. Thereafter, in this research natural element meshless numerical model (NEM) along with the Sibson’s interpolation was used for simulating seepage through the body of Droodzan dam. At first, in order to validating the NEM, simulation of flow in an embankment obstacle was done. After ensuring about the accurate operation of the numerical model, seepage simulation in the Droodzan dam’s body was applied and the results were checked with the observation data of dam’s piezometers. Regarding an average less than 5 for the relative error, the accuracy of the NEM can be concluded. Findings of the study confirm the inexistence of interior erosion or piping in the dam’s body as far as the internal drain of the dam is working properly.