In slightly more than a decade (1988-2000), the eminent issue for companies was one of attracting and retaining people with the skills necessary to do the work. The situation became even more complex during 2001 – 2009 period as an economic meltdown forced thousands of companies to cut back or downsize their employee populations. Employee turn-over is often associated with “employee retention”. Employee retention plays an important role to keep up with other companies amidst the rapid evolvement of global economic environment. The objectives of the study are (1) To identify and assess the factors affecting employee retention of private employees in Cambodia from the experts point of view such as HR practitioners etc. and (2) To recommend ways on how to improve employee retention. The researcher employed Delphi Method Technique with 2 rounds. The Delphi methodology is used to determine, predict and explore group attitudes, needs and priorities. The researcher invited 34 panel of experts who are at least middle managers of private companies in Cambodia such as HR professionals and managers and with at least 5 years of experience in the field. After round 2, the experts agreed that there are 5 factors greatly affecting employee retention of private companies in Cambodia and they are: compensation; promotion, opportunity and growth; work environment; training and development; and work-life balance.