Copyright © 2021 by ASME.Aerodynamic design of a forebody geometry has a significant effect on aircraft performance and stability. Although the studies conducted on aircraft performance so far, mostly, focus on optimization of wing-like structures, the contribution coming from an effective forebody design to the aircraft performance could be as high as the contribution coming from wing-like structures. A proper forebody design can reduce the wave drag and provide better lateral characteristics at high angles of attack. The reduced drag may enable the aircraft to achieve higher speeds and consume less fuel which eventually results in higher endurance and range to be achieved. On the other hand, achieving better lateral characteristics at high angles of attack may enable aircraft to withstand higher gust loads during take-off and landing phases. In addition to that, it may provide improved spin characteristics. In this paper, the forebody optimization of a jet trainer aircraft is studied. While doing so, two objectives are considered. Turbulent flow solutions are obtained with SU2. Response surface methodology is used as database generator and Pareto-optimal solutions are searched by using non-dominated sorting genetic algorithm-II. The optimization study improves the aircraft performance in the aspects of the wave drag and the lateral stability.