Energy extraction from tidal currents using marine current turbines has been gaining attention in recent years. In this paper, the design and optimization of a horizontal axis turbine is proposed to harvest available ocean kinetic energy from very low flow regimes, area of application which was not previously addressed in the literature. Accordingly, a horizontal axis marine current turbine is modeled and NACA 4 series airfoils are selected as the two-dimensional blade airfoils design domain. Blade geometry and airfoil shape are then optimized using response surface and steepest ascend methodology. At the end, the correctness and accuracy of the proposed design is compared with the developed turbine blade element momentum theory model which is demonstrated to be in an acceptable range.