Background and purpose: Previous studies have shown that smokers are deficient in social skills and it is possible that they have deficits in theory of mind. The aim of this study was to compare theory of mind and symptoms of attention deficit-hyperactivity between smokers and non-smokers.

Materials and methods: This study was conducted in 160 man (80 smokers and 80 non-smokers) who were selected by convenience sampling. Data was collected using the Persian version of Reading Mind from Voice (FVRMFV), Conners' Adult ADHD Rating Scale and a demographic questionnaire. Data was analysed in SPSS V. 16 applying multivariate analysis of variance and independent t-test.

Results: The findings showed higher scores of smokers in attention deficit (P<0.005), hyperactivity (P<0.006), impulsivity (P<0.007), problems in self-imagination (P<0.004), and whole range of ADHD symptoms (P<0.001) compared to non-smokers, but in mind reading test, smokers performed significantly weaker than non-smokers (P<0.001(.

Conclusion: Deficits in theory of mind is seen in smokers, therefore, deficits in social skills could be due to this reason in such groups.