Substance Use Disorders (SUD) and Attention Deficit Hyperactive Disorder (ADHD) are frequent conditions in out drug treatment centers. There are evidences about the high prevalence of ADHD in SUD patients (20%) compared with just ADHD in general population (1–7.3%). Both disorders and psychiatric comorbidity are important in the diagnosis proceeding. The objective of this study is search the difference in psychiatric comorbidity conditions between patients with ADHD and Cocaine SUD and ADHD and Cannabis SUD. ADHD was present in 158 patients of a total sample in which 46,8% used cocaine, 17.1% cannabis and 36.1% used both. Mood disorders were 26.8% in cocaine users, 21.7% in cannabis and 18.9% in both. Anxiety disorders were 20.3% in cocaine users, 37.5 in cannabis and 13% in both users. Primary psychotic disorders were 2.9% in cocaine users, none in cannabis and 11,1% in both drug users. Personality disorders by cluster were, Cluster A: 11.3% in cocaine group, 36% in cannabis group and 24.5 in cannabis and cocaine group. Cluster B: 33.8% in cocaine group, 44% in cannabis group and 51.9% in cannabis and cocaine group. Cluster C: 9.9% in cocaine group, 28% in cannabis group and 19.2% in cannabis and cocaine group. There could be common pathways of neuronal damage related to psychiatric comorbidity depending of used drug, the differences in comorbidity found in this study could explain a little part of it. It is important to manage SUD-ADHD and other psychiatric comorbidity in order to improve the outcomes of these patients.