The cause of most adult psychopathologies or behavioural disorders can be traced back to childhood. In this study, we examine the attention-deficit, fear and aggression in Iran's preschool students in Oshnaviye city. In this analytical-descriptive study, 50 students were selected through stratified sampling method from 249 students. Data were collected using a questionnaire about behavioural disorders and social threats. The validity of the research was 70.5%. The results showed that the average of attention-deficit in girls and boys was not very different. There was no significant difference in individual behaviour of girls and boys in the society. Problems such as poor concentration or indecisiveness and being afraid to try new things had the least prevalence. Finally, there was no meaningful difference in the level of attention-deficit, fear and aggression in Iran's male and female preschool students.