High strength concrete (HSC) has large application because of good performance and high durability. Optimizing mix proportions has main effect on the compressive strength of HSC. In this paper, optimizing mix proportions are investigated by Taguchi method, factors of water to cementitious material ratio (W/C), fine aggregate to total aggregate ratio (FI/AG), silica fume as supplementary cementitious material and cementitious material content were selected at three levels. After testing L9 orthogonal array and analyzing results by Taguchi method, the best optimized mix levels were predicted by Taguchi. Then optimum mix was constructed and tested. It was concluded Taguchi forecast is true about optimized mix levels.