Traditional houses are regarded as the best examples of energy efficient design due to their climate responsive design approach. Thus, traditional Diyarbakir houses in the hot-dry climate zone provide passively comfortable indoor environments without consuming excessive energy by their proper design parameters. Especially, during summer period, cooling loads are reduced by virtue of their climate responsive design despite high outdoor temperatures and intensity of solar radiation. In this study, the effect of solar heat gain on heating-cooling loads in courtyard buildings derived from central courtyard plan with different A/V ratios is evaluated. Moreover, the alterations of indoor conditions between seasonal parts, which are placed around the central courtyard in order to obtain optimum amount of solar gain, are analyzed. As a result, the efficiency of heating-cooling load provided by climate responsive design is aimed to be highlighted by considering the passive building performance of courtyard buildings in hot-dry climate zones in relation to solar heat gain.