This study examined the influence of substance abuse and personality factors on aggressive behaviour among Okada riders in Otukpo Local Government Area with Tthree hypotheses. A quantitative study using a cross-sectional survey design was conducted on 130 participants aged 16–35 years. Data were collected through a self- administered questionnaire using the Aggressive Driving Behavior Scale, Drug Abuse Screening Test, and Big Five Personality Traits Inventory. Statistical analysis was performed using regression analysis. Results revealed that substance abuse significantly influenced aggressive behaviour among Okada riders. Personality factors also had a significant impact on aggressive behavior. Additionally, there was a significant joint influence of substance use and personality factors on aggressive behavior among Okada riders in Otukpo Local Government Area. In conclusion, substance abuse and personality traits play a crucial role in aggressive behaviour among Okada riders. Therefore, the study recommends that the Federal Road Safety Corps and related organizations in Nigeria implement psychological intervention programs and regular enlightenment seminars, particularly targeting individuals with personality traits linked to aggression. These initiatives could help reduce substance use and, in turn, aggressive behaviour among Okada riders. The promotion of behavioural intervention programs, awareness campaigns, and stress management strategies is also recommended to improve their conduct on the road.