Objective: Studies about psychoactive substance use which is becoming more prevalent in the world and threatening humanity have increased. In this study, the results of 2015 substance use prevalence research are compared with 2003 and 2008 studies to examine the course of substance use in TRNC. Methods: The population of this study consists of Turkish speaking individuals who live in Turkish Republic of Northern Cyprus (TRNC) and are between ages of 18-65. The sample of 1040 individuals representing the general population was determined by stratified random sampling method by considering sex, age and geographical area quotas. The data was collected in May and June 2013. The survey form of the study was prepared from European Model Questionnaire of Council of Europe. Prevalence results are given compared with the data of 2003 (825 people) and 2008 (804 people) and used the same questionnaire. Results: At least once life-time cigarette use was 62.1% and alcohol use was 68.5%. The lifetime prevalence of any substance use other than cigarette and alcohol was 8.5% while illicit substance use was 8.4%. Illicit substance use rates were 3% in 2003 and 7.7% in 2008. Cannabis and synthetic cannabinoid bonsai which had been popular in recent years were found to be the most widely used illicit substances. Conclusion: The study shows that cigarette use in TRNC is higher than the rates of world average and alcohol use rates are parallel to western countries. An important increase in the rates of illicit substance use is found between the years of 2003-2013 in TRNC. [Anadolu Psikiyatri Derg 2017; 18(2.000): 99-107]