Since the building's problems in construction projects have increased, there is serious need to focus on the quality of building constructions industry. Even though Six Sigma has been employed in the manufacturing and other industries, it is quite a fairly new impression in the construction project. Therefore, a case study of how Six Sigma has been established in the building industry to identify problems of building projects in Amman. The main objectives of this case study to investigate the implementation of Six Sigma tools to investigate the main building's problems and the root causes of these problems. Also, the study intends to implement these tools to improve the performance and the efficiency of construction projects. To achieve this objective, the data is collected from government institutions to identify the main building problems and then the survey-based approach is used in order to identify the root causes of these problems. The main results of six sigma tools showed the main problems in building projects in Amman are excavation collapse, defective waterproofing system at the roof and bad drainage system of rainwater and lack of ventilation which represent 52.2% of total problems in building projects. Although the concept of using Pareto analysis and cause and effect diagrams have been around for a considerable period of time, the paper has successfully shown how can make use of these simple Six Sigma tools to find out the root causes of the problem and allocate resources to eliminate such problems.