Quality management system (QMS) provides generic guidance and requirements for establishing an appropriate quality management procedure, in order to lower cost, increase productivity, customer's satisfaction, and market share in the organizations since the last two-decade. In construction industry, it can assist the companies to achieve successfully their objectives, and ensure that all phases of construction project consistently meet client's requirements (need). The main aim of this article was to evaluate the impact of QMS implementation on main factors of construction projects in Metro Manila, Philippines. For this intention, the study was conducted an in-depth literature review from different books, journals, and websites, in order to understand profoundly quality management system, identify the characteristics of the vital factors of construction projects, and the findings of empirical studies concerning the effects of QMS on construction projects. Subsequently, a questionnaire was designed based on previous studies and then distributed randomly among the 37 managers with the aim of collecting data. Finally, the analysis of data was accomplished by descriptive statistics to find the results and conclusion. The findings have shown that the implementation of QMS can be affected mostly on customer's satisfaction, followed by cost, and time respectively, while minimum effectiveness of QMS was on scope (quality) through QMS implementation in construction projects in Metro Manila.