Abstract: This paper presents the methodology and steps for pit optimization of open pit mine using Geovia Whittle at the Husab Uranium Mine in Namibia, with emphasizing on the principles, methods and results of using Whittle"s advanced optimization module such as Blend Simulation and Cut-off Grade Optimization, to guide the optimization of the open pit project and enhance the project’s net present value. The results of the study show that Whittle can be used to efficiently complete and update the pit optimization and interim stage selection, to support the subsequent pit design. Whittle’s Blend Simulation verified the feasibility of meeting the long-term feeding grade requirements of 460 ppm to 700 ppm for the processing plant at the Husab uranium. Whittle"s cut-off grade optimization can increase the net present value of the Husab uranium project by 2.4% (approximately US37.0 million), extend mine life of two years, increase metal output of 1740 tonnes and increase processed ore of 1200 million tonnes.