A system to analyze, assess and manage the health performance of resources and spaces throughout the project lifecycle shall be established to ensure sustainable healthy buildings. Decisions made in the planning, design, construction, and operation and management (O&M) phases must help sustain the health performance of buildings at the level specified by clients or the relevant laws. For this reason, it is necessary to develop a model to ensure the consistent management of performance, as such performance varies according to the decisions made by project participants in each phase. The purpose of this research is to develop a Lifecycle Health Assessment Model (LHA) for sustainable healthy buildings. The developed model consists of four different modules: the Health-friendly Resources Database (HRDB) module, which provides health performance data regarding resources and spatial elements; the Lifecycle Health-performance Tree (LHT) module, which analyzes the hierarchy of spatial and health impact factors; the Health Performance Evaluation (HPE) Module; and the Lifecycle Health Management Module, which analyzes and manages changes in health performances throughout the lifecycle. The model helps ensure sustainable health performances of buildings.