Abstract Attention-deficit/hyperactivity disorder (ADHD) is a prevalent neurodevelopmental disorder in children and adults. In the substance use disorders (SUDs) population, ADHD prevalence reaches 23.1%, leading to more severe substance abuse progression and reduced treatment effectiveness. Cannabis is the most common illicit drug used among the ADHD population. The increasing popularity of medical marijuana (MM) has raised concerns about its potential impact on neurocognitive functions, particularly in adolescents. Persistent cannabis use can cause permanent changes in brain structures and circuits. This review aims to overview the comorbidity of ADHD and SUDs, focusing on cannabis use disorders. Theoretical models of the etiologies of ADHD and SUDs...