A method based on non-uniform rational B-spline (NURBS) surface technique coupled with mesh deforming technique was developed to design the profiled endwall for turbines cascade. This method has the advantages of flexible geometry representation and automatic rapid remeshing. An optimal design procedure of profiled endwall has been developed by integrating the commercial CFX solver and the optimization driver Isight. This procedure was applied to optimal design the profiled endwalls of Pack B turbine cascade. The total pressure loss coefficient of turbine cascade was reduced by 12.96% after optimization. The results show that the static pressure field on the endwall of turbine cascade is changed, so the horseshoe vortex and the passage vortex in turbine cascade passage are weakened. Therefore, the aerodynamic performance of the turbine cascade is improved.