In this paper two dimensional unsteady flow is simulated by shallow water equations (SWE). The governing equations is solved by Finite Volume Method (FVM) in explicit conditions. In order to discretization of 2D SWE’s unlike other researchers that prefer to use Riemann solvers, total variation diminishing (TVD) schemes is applied directly in the unstructured mesh systems. In the sake of testing the numerical results, Flow3D software has been used. The comparison between numerical results of developed model and explicit and implicit solutions of Flow3D shows good agreement.