Background: Substance abuse refers to the use of all chemicals, drugs and industrial solvents that can produce dependence (psychological and physical). It can also refer to repeated non-medical use of potentially addictive chemical and organic substances. According to UNICEF and WHO, substance abuse includes the use of chemicals in excess of normally prescribed treatment dosage and frequency, even with knowledge that they may cause serious problems and eventually lead to addiction. Hence, this study was done to determine the prevalence of substance abuse among students in University of Port Harcourt host’s communities. Materials & Methods: The study was a descriptive cross-sectional study carried out in ALUU Community in Ikwerre Local Government Area of Rivers State. The study involved 150 volunteers recruited randomly through a multi-staged sampling technique which included secondary school students, undergraduates and post graduates who are 13yrs and above residing in ALUU community while, those who did not give consent were excluded. The data was collected using a self-structured close-ended self-administered questionnaires and data analysis done using SPSS version 25. Results and Discussions: The most frequent age category was 20-24years (42.67%), while the least frequent category was 10-14years. The most frequent gender (sex) was the males (71.33%); the most frequent educational level was undergraduate 84.67%. The study again showed that the most commonly abused substances by students were alcohol 90.57%, Nicotine 39.62%, while the least abused drugs were heroin and cocaine being 1.89% respectively. The prevalence of drug abuse seen in the study was 35.33%. Moreover, the distribution of known acquaintance of persons who abuse drugs was 78.67%. Conclusion: The prevalence of drug abuse seen in the study was 35.33%. Peer group, neighbourhood influence and parents habits of drug/substance abuse were the attributed contributing factors to the prevalence of drug/substance abuse amongst students in Aluu.