Given the variety of actions concentrating on peacekeeping with significant successful operations, the United Nations (UN) continues to encounter concerns and challenges that have hampered its peacekeeping operations’ efficiency, effectiveness, and performance. This article aimed to investigate the primary challenges that adversely influence peacekeeping operations and challenge them based on the security theory proposed by Barry Buzan. According to the study’s findings, UN peacekeeping missions have been successful in addressing conflict situations and promoting peace in many regions of the world. Nevertheless, faults and challenges, notably in terms of the operations’ political, economic, and societal factors, have restricted the peacekeeping operations’ ability to achieve their objectives successfully. Therefore, a better policy that includes all involved actors, especially local government and the population, should be established in order to rebuild a conflict-torn country.