Latent heat thermal energy storage technologies based on phase change materials (PCMs) are found to be significantly efficient and viable methods for thermal energy storage. These energy storage techniques have been proved to be with positive effects on buildings energy efficiency. The integration of appropriate thermal energy storage system and selection of suitable PCMs plays a very dominating role in the upgrading of energy efficiency. Short and long term storage helps in the reduction of energy demand or shifting peak load for both heating and cooling. However, a comprehensive study for the application of these technologies adopting Vietnamese built environment is lacking which can relate to climate, energy storage, and energy efficiency. By using EnergyPlus, this research wants to make a specific calculation in energy saving by comparing the energy consumption of model with and without installing PCMs. Besides that, the reduction of shift peak energy demand can decrease the size and initial cost of heating or cooling systems, lower energy costs, and reduce maintenance costs. The research use assumed data from case study included dimension, construction layers, location… as well as real climate date of location for all simulation. The results show that many PCMs and techniques are promising to be used in Vietnam. By using the dissertation’s results, designers can reduce the time for calculations and improve the efficiency of energy saving in their design. Investment cost has been analyzed based on Vietnam case study building. Therefore, this research will give the conclusion and suggestion for economic efficiency of investors. The cost analyzing work serve as references and for further research about Phase Change Material.