Documented empirical evidence indicates that substance abuse among young people, especially students, is assuming an unprecedented upward surge worldwide. Substance abuse among students is associated with a myriad of negative physical, social and psychological consequences, including liver, cranial, and cardiovascular diseases, cancers, vehicular fatalities, mental and behaviour disorders, violence, declining grades, increased potential for dropout and high truancy rates, suicides, homicides, and accidental injuries. Indeed, substance abuse is now considered a leading cause of preventable deaths in many countries of the word. Although there is preponderance of studies on substance abuse among students, there is lack studies on personality and demographic factors. In this cross-sectional survey, we explored the extent to which capacity to delay gratification, core self-evaluations and demographic variable would predict substance use among students (n=325) of a state-owned, non-residential Nigerian university. A structured questionnaire was used to collect relevant data. Results of multiple regression showed that a combination of the predictor variables jointly predicted substance abuse by accounting for about 22% of its variance. Independently, gender, age, family background (β=.23; p<.01), birth order, delayed gratification and core self-evaluations predicted substance abuse. It was recommended that youths should be taught the benefits inherent in delaying gratification. Psycho-educational and skill-building programmes should be used to re-orient students about substance abuse.