This study investigates performance-based design optimization for a Kaplan hydro turbine at a maximum water head of 2.6 m (8.5 ft), a micro-sized horizontal Kaplan turbine with 7.6 cm (3.0 in) diameter that has fixed blades featured to attain the optimum performance for such type and size of hydro turbines. The optimization process includes solving design problems and enhance design development by applying a multi-disciplinary design optimization (MDO) technique. Varying the geometrical parameters of the turbine, i.e., dimensions, number of blades, blade wrap angles, and different rotational speeds (500–3000 rpm), are the relevant proposed disciplines of this study. Two multi-simulation matrices were solved by using the high-performance computing (HPC) cluster of the University of Wisconsin-Milwaukee. The first matrix includes different number of the blades (3, 4, 5, 6, and 7 blades) over six different rotational speeds (500, 1000, 1500, 2000, 2500, and 3000 rpm), while the second matrix includes 121 possible combinations of blade wrap angles starting at 60–60 deg (hub-shroud) angle to 110–110 deg angle with 5 deg increment alternated at both sides, the hub and the shroud.