This study examined the knowledge hiding behaviour (KHB) of undergraduates of a university in southwestern, Nigeria, as well as the individual and social factors influencing their knowledge hiding behaviour. The study adopted the descriptive survey design. Random sampling was used to select 390 undergraduates across the faculties of the university. A structured questionnaire was used to collect data. Findings revealed that the undergraduates engaged in knowledge hiding. The study also identified the various methods the students used to hide knowledge, among which are pretense of lack of knowledge, avoiding interactive classes, reading alone and unwillingness to release lecture notes, among others. The results show that the individual factors (distrust and psychological ownership), as well as the social factors (negative or lack of mutual reciprocity, lack of social interaction and lack of social identification), predicted the KHB of the students. The study concluded that the undergraduates engaged in knowledge hiding in so many ways and for many reasons. The individual factors of the students, as well as the social factors surrounding them, predicted their KHB. The study made some recommendations for research and practice.