Results of the current study showed that EI training led to reduction of the illicit drug use potential (P < 0.001; 95%CI: 2.253 - 12.433). The study by Nadalinezhad et al. showed that EI training reduced the illicit drug use potential in the youth (
5). Various studies on students (
9), addicts (
10), and adults (
11,
12) indicate an inverse relationship between EI and the illicit drug use potential. However, the results of the current study were not consistent with those of the study by Harakeh et al. (
13). This difference could be due to the age and population difference between the studies. People with high EI have the ability to understand and analyze their own and others’ emotional experiences, and this enables them to regulate their emotions and resist developing bad habits such as addiction (
9). Moreover, Albein-Urios’s study showed that the inability to properly control emotions is an important factor in the illicit drug use potential (
14). A study by Stappenbeck and Fromme confirmed that training these skills led to the prevention of alcohol consumption and negative emotions (
15). Moreover, there was a direct relationship between EI and the relapse rate of addiction (
16). The present study also found that EI can be an important factor in explaining and predicting the illicit drug use potential among nurses, which was consistent with the results of Ghanbari et al. (
9). The study by Coelho showed that the subjects with a higher EI exhibit less of a propensity to consume tobacco and alcohol (high-risk behaviors) (
17). Additionally, the results of previous studies indicated a significant difference between the EI of addicts and non-addicts. In other words, addicts had a higher social intelligence. But, it was the first study that assessed this issue in the Iranian nurses.