A two-dimensional and quasi-stationary numerical model is presented to study the fluid flow and the heat transfer in high power density keyhole welding process. A recently developed method of the position-correction is employed to accurately identify the solid-liquid interface location during welding. A parametric analysis of the existing keyhole model is performed, and the effect of parameters such as material properties, welding speed, keyhole radius on the heat transfer is analyzed during keyhole welding process.