The Beijing-Tianjin-Hebei (BTH) megaregion, a fundamental core economic region of China, is of great strategic significance. However, dramatic landscape urbanization has resulted in a growing threat to the eco-environment, such as an obvious decrease of arable land, water resource shortages, environmental pollution, etc., which has severely restricted future regional socio and economic development. Thus, land allocation optimization across the entire megaregion is an urgent issue challenging regional planners and decision-makers. In this study, we used the BTH megaregion to develop a research framework to integrate a multi-goal optimized and spatial configuration model to simulate an optimized land use allocation scenario by balancing the socio, economic, and ecological goals in 2020. We found that: 1) a multi-objective generic algorithm is suitable for multi-objective land use structure optimization and provides a foundation to predict changes in multi-objective land use structures; 2) by integrating the optimized schemes based on the genetic algorithm and CLUE-S model, an optimized land use allocation scenario could be established; 3) by comparing the similarities and differences between the optimized and non-optimized land allocation scenarios, we found that in the optimized scenario forest land increased more significantly and degradation of cultivated land decreased, which reduced encroachment into important ecological land and met the purpose of optimizing the land use structure. Both the research framework and findings of this study could support the planning and decision-making for the synergetic development of the Beijing-Tianjin-Hebei megaregion.