The need for organization to achieve its corporate objectives brought about the adoption of manpower planning in their management process. It is hoped that effective manpower planning of their employees would enhance their performances thereby contributing effectively in achieving organizational objectives. The research examines the impact of manpower planning on achievement of corporate objectives of an organization (A case study of Delta Glass Company Plc, Ughelli.) and its impact on both the employees and the organization as a whole with a specified objective of looking at its contributions to achieving its corporate objectives via the improvement of skill and knowledge of staff in an organization to enhance job satisfaction. In conducting the research work, personal interviews and questionnaires method were used in data collection and data analysis was on simple percentage method which was administered to a sample 100 staff in an organization. Literature relevant to the study was extensively reviewed. This research work is important since worker’s performance directly or indirectly depends on how well an organization plans its manpower. From the findings of the research, the following recommendations were made: Every organization should endeavour to give manpower planning the attention it desires. Specialists in this area of manpower planning should be employed in companies/ organizations to handle this complex assignment so that the fruits of an effective manpower planning can be reaped by such organizations.