AbstractSpace–time behavior research is an important branch of geography research that focuses on micro individual space–time behavior and macro urban social structure and their interactions. It plays an important role in urban public policy making. In this paper, an attempt is made to introduce the theory of space–time behavior research in urban design and probe into the spatial method of realizing urban humanism. Taking the urban design masterplan of Huairou Science City (HSC), this study discusses a framework of the layout evaluation and optimization strategy mainly for the greenspace system in HSC’s masterplan, based on the extent to which the layout of the greenspaces can be adapted to the behaviors of HSC’s users. The main content of this paper starts with an introduction to the hypothesis of the Behavior-Layout Integrated Evaluation and Planning (BLIEP) model and expounds on its foundation and potential principles or methods; under this model, this study takes HSC’s masterplan as an example, carrying out an analysis on the space–time behaviors of HSC’s users and conducting the behavior-integrated evaluation and optimization planning for the layout of greenspaces. It has been identified that some greenspaces, especially community greenspaces, cannot be fully adapted to users’ behaviors and activity demands due to the morphological or visual pursuit in their layouts. Thus, the optimization work is supposed to be done. This paper demonstrates the predicament of the traditional layout of greenspaces over the neglect of user-friendliness and makes an attempt under the tendency for greenspaces in green corridors or urban fabric to scatter by integrating the behavioral space into the built environment. Ultimately, further discussions are focused on upgrading the model and its extended application to other aspects in urban design.