Building Information Modeling (BIM) technique is one of the modern techniques that have become widely used in many areas of the construction sector, including energy management. This work aims to study the effect of sun path analysis in improving energy performance, analysis and evaluation of the energy performance based on the tools provided by BIM technique, and comparison of simulated electrical energy results with real electrical energy consumption. The criteria of this study applied on one Iraqi project at Diyala University. The results illustrate that BIM very useful to perform various analyses helped to find different strategies for improving the energy efficiency of the project such as sun path analysis and Green Building studio (GBS) tool based on BIM technique useful tool to energy analysis where the result illustrate most electricity consumption goes for cooling space with consumption around (63871) kWh in August month as well as most fuel consumption for the purpose of space heating with consumption around(187846) MJ in December. GBS tool based on BIM technique is an effective tool that can help designers and architects in energy performance assessment as well as calculate energy costs in the early design stage, also it helps in finding the best solutions that contribute to improving energy efficiency in the early stages of the project life cycle.