This project is on Effect of substance abuse among youths in Ilorin metropolis of Kwara state. Drug/substance abuse is one of the major problems confronting the nation today especially among the youth. Incidences of drug/substance and alcohol abuse and related anti-social behavior have tremendously increased in recent years. This has become a matter of concern to the government, parents, teachers, non-governmental organizations and all other relevant agencies. The Nigeria government has recognized the seriousness of the drug/substance problem, this is the reason why most of the drugs are prohibited by law and there national and international agencies established for the purpose of monitoring and controlling the illegal drug trade. In 1980, the Federal Government established the National Drug Law Enforcement Agency (NDLEA) to fight drug abuse and trafficking in the country and initiated the National Campaign against Drug/substance Abuse (NACADA) in early 2001. This present study found that drug/substance use and abuse among youth are increasing despite the control mechanisms that have been put in place. The study recommended that, as a first step to prevent and control drug/substance abuse, parents should be sensitized on the dangers of drug/substance abuse, the attendant problems and their functions as role models. Furthermore, schools should have a drug/substance prevention curriculum from Kindergarten onwards teaching that drug/substance use is wrong and harmful. There is also the need for initiation of rehabilitation programmes for drug/substance dependent persons.