The achievement of national cohesion is one of the issues confronting Nigeria as a nation. The study therefore assessed challenges and the role of school management in students’ behavioural modifcation for the enhancement of national cohesiveness. The investigation was conducted in the University of Abuja. Two objectives and research questions guided the study and descriptive survey research design was adopted for the study. The population consisted of six hundred and ninety (690) students from the Department of Educational Administration and Planning of the University of Abuja. The sample consisted of 360 students that were randomly selected from among the students of the Department of Educational Administration and Planning of the University of Abuja. A questionnaire titled “Challenges and Management’s Role in Students’ Behavioural Modifcation” (CMRSBM) was used as instrument for data collection. The researcher found among others that unhealthy relationship among various ethnic groups, favoritism on ethno-religious ground by some management staﬀ aﬀect the achievement of national cohesiveness negatively. Also, it was revealed that the school management play active role in modifying students’ behaviour for national cohesion. Recommendations were made among which include that school management should ensure good governance at all facets of the school administration and they should show leadership by example.