In order to know the prevalence of head louse among the school children in rural area, we visited 3 primary schools and a kindergarten in Sanbuk-myon, Mungyong-gun, Kyongsangbuk-do in July 1985, and examined the children to identify the adult worms of head louse and/or its nits on the hair. The overall infestation rate was 91.9% among 420 children examined, and there was a difference between schools (P < 0.05). the school girls' rate, 96.1% was higher than that of bods' 88.9%(P < 0.05). By grade, the rate of infant school was 88.5% and 1st to 6th grade were 100, 100, 95.8, 90.4 89.7, 80.0% respectively. Above result indicates that the head louse is an important health problem in this community. Therefore, the chemotherapy and the effort to improve the hygiene are necessary in this community by physicians, teachers and health administrators.