Objective: To investigate the prevalence of head lice in primary and middle school children in Asadabad, Iran. Methods: This study is an analytical descriptive cross-sectional one conducted among primary and middle school children in Asadabad during the academic year of 2013-2014. Data were collected at baseline via questionnaire, checklist and head examination. Results: A total of 600 students were examined (412 girls and 188 boys), and 14 students showed pediculosis. And the total prevalence rate was 2.3% (3.2% girls and 0.5% boys). The infestation was equal in public and private schools. The rate of pediculosis was higher in students of primary schools (4.0%) than those in middle schools (0.7%). The age of the students ranged from 6 to 14 years. The total number of infected group was 14 with mean age of 8.93 ± 2.43 years, and it was 586 with mean age of 10.98 ± 2.82 years for the uninfected group who were enrolled in the study (P < 0.01). This study showed significant differences between students with curly hair (5.5%) and those with straight hair (1.9%) when compared in terms of head lice infestation (P < 0.05). The relations of pediculosis and other socioeconomic factors such as sharing common comb and a room with other people, frequency of bathing, and parents' profession and education were analyzed, and Chi-square test did not show a statistically significant relationship between head lice contamination and the abovementioned socioeconomic factors (P > 0.05). Conclusions: It is necessary to find the risk factors of the infection in order to understand how to control or decrease infection in students, considering the important role of health education in reduction of head lice infections.