Finite Element Simulation of two-dimensional laminar steady state natural convection in a rectangular open cavity has been studied. A heated circular cylinder is placed at the centre of the cavity where the left sidewall to the cavity is heated by a constant heat flux. The top wall is kept cool and the bottom wall is kept at a hot temperature. The fluid is concerned with different Prandtl numbers. The properties of the fluid are assumed to be constant. The physical problems are represented mathematically by different sets of governing equations along with the corresponding boundary conditions. In this study, finite element method for steady state incompressible natural convection flows is used to find the numerical results. The Galerkin Weighted Residual method of finite element formulation is applied to discretize the non-dimensional governing equations. The results of the investigation are obtained in terms of streamlines, isotherms and heat transfer characteristics Nusselt numbers for different Grashof numbers and different inclination angles of the cavity ranges from 0o to 45o.