Introduction: Despite progress in health, human lice are still considered as a health problem. Lice could transmit different diseases to human such as epidemic relapsing fever, epidemic typhus and trench fever. The aim of this study was to determine the major factors on pediculosis capitis in students of Pakdasht county in autumn of 2013.

Methods: This was a cross-sectional descriptive and analytic study. Among all students, after investigating in terms of pediculosis, 678 infested individuals were selected. The extracted data were analyzed by using SPSS version 20 software and Chi-square test.

Results: From total number of 53732 students in different school grades, 556 females (82%) and 122 males (18%) were found to be infested by head lice. A significant relationship was recognized between the rate of infestation and students’ gender (P<0.001). The result, furthermore, revealed that rate of infestation in elementary students (73.1%) was significantly higher than other grades (P=0.03). Between mother’s education level and the infestation rate, moreover, a statistically significant correlation was seen (P=0.04).

Conclusion: The results illustrate that head lice infestation, as a major problem, is related to some factors including economic conditions and poor education. To find strategies for this issue, regarding its cultural, economical and social aspects, cooperation of different organs like ministries of education and health and also students and their parents is clearly required.