There exists a well-known gap between predicted and actual performance of energy-efficient buildings. In order to maintain the performance of energy-efficient building in Malaysia, a comprehensive evaluation method is needed to analyze energy-efficient design from user's perspective. However most of the evaluations research done on energy-efficient building performance is not comprehensive enough; those studies are only focused on users' attitude toward building performance criteria. A comprehensive building performance diagnostic technique, Post Occupancy Evaluation (POE) may surpass the comprehensives of the current evaluation method and reduce the gap between users and building's energy-efficient design. For these reasons, the aim of this research is to evaluate the performance of energy-efficient building in Malaysia by identifying the problems affecting the performance of energy-efficient design through POE. The objectives of this research are to establish critical user satisfaction of energy-efficient design; to identify inefficiency of building performance in term of energy-efficient design; and to investigate the problems causing the inefficiency of energy-efficient design. This research will be conducted in three energy-efficient buildings in Malaysia; they are Ministry of Energy, Communications, and Multimedia office building, Energy Commission office building and Malaysia Green Technology Corporation office building. POE is chosen as the method of data gathering and questionnaire will be distributed to the technical staffs of the selected building. The feedback from the technical staffs will be analyzed by using Statistical Package for the Social Science (SPSS). Hopefully the research outcome could contribute to the development of energy-efficient design for energy-efficient building through the identification of inefficiency of the existed building.