Transom stern flow is a complicated fluid flow phenomenon especially at high speed regime. Therefore, various authors have studied the transom stern flow, both numerically and experimentally. Smoothed Particle Hydrodynamics method can be considered as a good choice for simulation of nonlinear physics related to the transom flow. Accordingly, SPH as a meshless, Lagrangian, and particle method is presented in this article and SPS turbulent model is also included for more accurate solution. For density modification, a second order density filter scheme is employed. For validation of numerical setup, several draft based Froude numbers are considered and it is shown that SPH solution is in good agreement with available experimental data. Furthermore, three longitudinal Froude number are investigated for high speed transom flow simulation. High speed cases are compared with Savitsky's formula and it is observed that at high speeds, SPH solutions are also reasonable.