This paper presents results of identifying critical factors affecting process groups of the project management processes of construction projects in Vietnam. The study collected data from individuals working on construction projects in Hanoi. This study ranked factors using the Relative Influential Index (RINI) from different viewpoints of stakeholders. The study found that two leading critical factors are associated with the initial stage and three with the controlling stage from an overall viewpoint. This information implies that stakeholders of construction projects in Vietnam are often concerned about the initial and controlling phases. Moreover, the least influential factors are associated with the planning stage. This is very intriguing. These findings may be used as a guideline to develop appropriate strategies so that project stakeholders of construction projects in Vietnam improve the efficiency of project management processes.