Introduction: Despite progress in health and medical sciences, human lice are still considered as a health problem. The aim of this study was to investigate the prevalence and factors associated with its pediculosis in Central Prison of Hamadan in 2013.

Methods: In this descriptive and analytical cross sectional study, from 2900 male prisoners, 384 were selected by the systematic method. After reviewing in terms of pediculosis infection, the extracted data were analyzed by using SPSS software version 20.

Results: The study showed that 5.2% of the prisoner was infected with louse. Most infections were observed in the age group of 30-39 years old, and the lowest in the group of 20 years old and less (P>0.05). The highest rate of pediculosis was seen in the people had drug addiction, and buying and selling, no specific bed, common use of bed and blankets, bath once and less per week (P<0.05). Comparison of Age, a period of imprisonment, level of education and number of prisoners in room, between healthy and infected people showed no significant difference (P>0.05). Most cases of infected with lice were in the head (85%), body (10%) and pubic (5%).

Conclusion: Considering the results of this study, it can be said that the conditions of the prison, including density, the type of crime and lack of hygiene and the use of personal devices are highly associated with the prevalence of pediculosis.