Human resource planning ensures that the right number of people is in the right jobs at the right time to meet the set goals and objectives. At the national level, a well-planned human resource is seen as the foundation for economic growth. Human resource plan can specify the future national workforce requirement indicating any shortage or surplus of the supply. Though forecasting the quantity and quality of human resource requirements, based on a model is essential, to date, no study has been carried out to estimate workforce requirements at the national level in Sri Lanka. Therefore, this study is an attempt to address this research gap. It is expected that the findings of this study will have broader relevance at national level policy planning.